Top Banner
First-in-Class ERK1/2 Inhibitor Ulixertinib (BVD-523) in Patients with MAPK Mutant Advanced Solid Tumors: Results of a Phase I Dose-Escalation and Expansion Study Ryan J. Sullivan 1 , Jeffrey R. Infante 2 , Filip Janku 3 , Deborah Jean Lee Wong 4 , Jeffrey A. Sosman 5 , Vicki Keedy 5 , Manish R. Patel 6 , Geoffrey I. Shapiro 7 , James W. Mier 8 , Anthony W. Tolcher 9 , Andrea Wang-Gillam 10 , Mario Sznol 11 , Keith Flaherty 1 , Elizabeth Buchbinder 7 , Richard D. Carvajal 12 , Anna M. Varghese 12 , Mario E. Lacouture 12 , Antoni Ribas 4 , Sapna P. Patel 3 , Gary A. DeCrescenzo 13 , Caroline M. Emery 13 , Anna L. Groover 13 , Saurabh Saha 13 , Mary Varterasian 13 , Dean J. Welsch 13 , David M. Hyman 12 , and Bob T. Li 12 RESEARCH ARTICLE Cancer Research. on December 17, 2020. © 2018 American Association for cancerdiscovery.aacrjournals.org Downloaded from Published OnlineFirst December 15, 2017; DOI: 10.1158/2159-8290.CD-17-1119
13

Two diseases, same person: moving towards a combined HIV and … · 70% and HIV prevalence among persons with presumptive TB (i.e. patients with TB symptoms but who may have a different

Aug 26, 2020

Download

Documents

dariahiddleston
Welcome message from author
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
Page 1: Two diseases, same person: moving towards a combined HIV and … · 70% and HIV prevalence among persons with presumptive TB (i.e. patients with TB symptoms but who may have a different

First-in-Class ERK1/2 Inhibitor Ulixertinib (BVD-523) in Patients with MAPK Mutant Advanced Solid Tumors: Results of a Phase I Dose-Escalation and Expansion Study Ryan J. Sullivan 1 , Jeffrey R. Infante 2 , Filip Janku 3 , Deborah Jean Lee Wong 4 , Jeffrey A. Sosman 5 , Vicki Keedy 5 , Manish R. Patel 6 , Geoffrey I. Shapiro 7 , James W. Mier 8 , Anthony W. Tolcher 9 , Andrea Wang-Gillam 10 , Mario Sznol 11 , Keith Flaherty 1 , Elizabeth Buchbinder 7 , Richard D. Carvajal 12 , Anna M. Varghese 12 , Mario E. Lacouture 12 , Antoni Ribas 4 , Sapna P. Patel 3 , Gary A. DeCrescenzo 13 , Caroline M. Emery 13 , Anna L. Groover 13 , Saurabh Saha 13 , Mary Varterasian 13 , Dean J. Welsch 13 , David M. Hyman 12 , and Bob T. Li 12

RESEARCH ARTICLE

Cancer Research. on December 17, 2020. © 2018 American Association forcancerdiscovery.aacrjournals.org Downloaded from

Published OnlineFirst December 15, 2017; DOI: 10.1158/2159-8290.CD-17-1119

Page 2: Two diseases, same person: moving towards a combined HIV and … · 70% and HIV prevalence among persons with presumptive TB (i.e. patients with TB symptoms but who may have a different

february 2018 CANCER DISCOVERY | 185

ABSTRACT Ulixertinib (BVD-523) is an ERK1/2 kinase inhibitor with potent preclinical activity in BRAF- and RAS-mutant cell lines. In this multicenter phase I trial (NCT01781429),

135 patients were enrolled to an accelerated 3 + 3 dose-escalation cohort and six distinct dose-expan-sion cohorts. Dose escalation included 27 patients, dosed from 10 to 900 mg twice daily and estab-lished the recommended phase II dose (RP2D) of 600 mg twice daily. Ulixertinib exposure was dose proportional to the RP2D, which provided near-complete inhibition of ERK activity in whole blood. In the 108-patient expansion cohort, 32% of patients required dose reduction. The most common treatment-related adverse events were diarrhea (48%), fatigue (42%), nausea (41%), and dermatitis acneiform (31%). Partial responses were seen in 3 of 18 (17%) patients dosed at or above maximum tolerated dose and in 11 of 81 (14%) evaluable patients in dose expansion. Responses occurred in patients with NRAS- , BRAF V600–, and non–V600 BRAF -mutant solid tumors.

SIGnIFICAnCE: Here, we describe the fi rst-in-human dose-escalation study of an ERK1/2 inhibitor for the treatment of patients with advanced solid tumors. Ulixertinib has an acceptable safety profi le with favorable pharmacokinetics and has shown early evidence of clinical activity in NRAS - and BRAF V600- and non-V600–mutant solid-tumor malignancies. Cancer Discov; 8(2); 184–95. ©2017 AACR.

See related commentary by Smalley and Smalley, p. 140.

1 Massachusetts General Hospital Cancer Center, Harvard Medical School, Boston, Massachusetts . 2 Sarah Cannon Research Institute, Tennessee Oncology, Nashville, Tennessee. 3 The University of Texas MD Anderson Cancer Center, Houston, Texas. 4 University of California, Los Angeles, David Geffen School of Medicine, Los Angeles, California. 5 Vanderbilt University Medical Center, Nashville, Tennessee. 6 Sarah Cannon Research Institute, Florida Cancer Specialists, Sarasota, Florida. 7 Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts. 8 Beth-Israel Deaconess Medical Center, Boston, Massachusetts. 9 South Texas Accelerated Research Therapeutics, San Antonio, Texas. 10 Washington University in St. Louis, St. Louis, Missouri. 11 Yale University, New Haven, Connecticut. 12 Memorial Sloan Kettering Cancer Center, New York, New York. 13 BioMed Valley Discoveries, Inc., Kansas City, Missouri. note: Supplementary data for this article are available at Cancer Discovery Online (http://cancerdiscovery.aacrjournals.org/). R.J. Sullivan, J.R. Infante, and F. Janku contributed equally to this article. Current address for J.A. Sosman: Northwestern University Medical Center, Chicago, Illinois; current address for R.D. Carvajal: Columbia University Medical Center, New York, New York; and current address for S. Saha: Atlas Venture, Cambridge, Massachusetts. Corresponding Authors: Ryan J. Sullivan , Massachusetts General Hospital Cancer Center, 55 Fruit Street, Boston, MA. Phone: 617-724-4000; Fax: 617-726-1949; E-mail: [email protected] ; and Bob T. Li, Tho-racic Oncology Service, Division of Solid Tumor Oncology, Department of Medicine, Memorial Sloan Kettering Cancer Center, and Weill Cornell Medical College, 885 2nd Avenue, Suite 1032, New York, NY 10017. Phone: 646-888-4201; Fax: 646-227-7276; E-mail: [email protected] doi: 10.1158/2159-8290.CD-17-1119 ©2017 American Association for Cancer Research.

INTRODUCTION MAPK signaling via the RAS–RAF–MEK–ERK cascade plays

a critical role in oncogenesis. As the terminal master kinase of this MAPK pathway, ERK1/2 infl uences cellular proliferation, differentiation, and survival through a variety of mechanisms ( 1 ). Aberrations of MAPK/ERK pathway components are ubiquitous across numerous cancer types. Mutations in RAS family genes ( KRAS and NRAS ) occur in approximately 30% of all human cancers ( 2 ), with KRAS mutations prevalent in pan-

creatic (>90%; ref. 3 ), biliary tract (3%–50%; ref. 4 ), colorectal (30%–50%; ref. 5 ), lung (25–30%; ref. 6 ), ovarian (15%–39%; ref. 7 ), and endometrioid endometrial (18%; ref. 8 ) cancers, and NRAS mutations prevalent in melanoma (20%; ref. 9 ). Muta-tions in RAF family genes, most notably BRAF at codon V600, are frequent, particularly in malignant melanomas (50%; ref. 10 ), and in approximately 7% of a wide range of other cancers ( 11 ). Atypical BRAF alterations (non-V600) occur sporadically across numerous tumor types. Insight into the mechanism of action of such alterations is developing, with the understand-ing that BRAF V600 alterations can act as monomers to drive signaling, whereas specifi c atypical BRAF non-V600 altera-tions act in a dimer-dependent manner ( 12 ). Approved BRAF inhibitors (vemurafenib and dabrafenib) are effective in BRAFV600–driven tumors, but have not been shown to be effective against BRAF non-V600 mutations. Mutations in MEK or ERK are rare, with reports for MEK mutations occurring in 5% to 8% of melanomas ( 10, 13 ), and ERK mutations occur-ring in cervical cancer (8%; ref. 14 ) and head and neck squa-mous cell carcinoma (1.5%; ref. 15 ). Collectively, activating mutations of MAPK/ERK pathway components are frequent events in a range of cancer types. Therefore, downstream inhi-bition of ERK is an attractive therapeutic avenue to pursue.

Precedence for targeting the MAPK/ERK pathway has been established for treatment of BRAF V600–mutant melanoma and lung cancers, where combined BRAF and MEK inhibition is now standard of care following FDA approval of dabrafenib plus trametinib ( 16, 17 ) and vemurafenib plus cobimetinib ( 18 ). Furthermore, favorable phase III data have been described for encorafenib plus binimetinib ( 19 ). Initially, BRAF inhibitor monotherapy was shown to be effective ( 20 ), yet the addition of MEK inhibition not only attenuated BRAF inhibitor–associ-ated toxicities but also improved overall response rates (ORR), progression-free survival (PFS), and overall survival (OS; refs. 16–18 ). The combination of BRAF/MEK inhibitor therapy now has been studied in a number of BRAF V600E–mutant

Cancer Research. on December 17, 2020. © 2018 American Association forcancerdiscovery.aacrjournals.org Downloaded from

Published OnlineFirst December 15, 2017; DOI: 10.1158/2159-8290.CD-17-1119

Page 3: Two diseases, same person: moving towards a combined HIV and … · 70% and HIV prevalence among persons with presumptive TB (i.e. patients with TB symptoms but who may have a different

Sullivan et al.RESEARCH ARTICLE

186 | CANCER DISCOVERY february 2018 www.aacrjournals.org

solid-tumor malignancies with varying results, ranging from melanoma-like outcomes in lung cancer (17) to only rare responses in colorectal cancer (21), and intermediate results in thyroid cancer (22). Additionally, although it has been dem-onstrated that BRAF/MEK inhibitor–targeted combination therapy provides significant additional benefit beyond single-agent options in melanoma and other cancers, the majority of patients eventually develop resistance and disease progression after approximately 12 months (16, 23, 24). Several mechanisms of acquired resistance following either single-agent or combina-tion therapies have been identified, including, but not limited to, the generation of BRAF splicing variants, BRAF amplifica-tion, NRAS or MEK mutations, and upregulation of bypass pathways (25–31). Central to these mechanisms of resistance is the reactivation of ERK signaling, which enables the rapid recovery of MAPK pathway signaling and escape of tumor cells from single-agent BRAF inhibitors or combination BRAF/MEK inhibitor therapies (32, 33). Therefore, ERK inhibition may provide the opportunity to avoid or overcome resistance from upstream mechanisms, as it is the most distal master kinase of this signaling pathway. This is supported by preclinical evidence that inhibition of ERK by small-molecule inhibitors acted to both inhibit the emergence of resistance and overcome acquired resistance to BRAF and MEK inhibitors (34–39).

Ulixertinib (BVD-523) is a highly potent, selective, reversible, ATP-competitive ERK1/2 inhibitor that has been shown to reduce tumor growth and induce tumor regression in BRAF- and RAS-mutant xenograft models. Furthermore, single-agent ulixertinib was found to inhibit tumor growth in human xeno-graft models that were cross-resistant to both BRAF and MEK inhibitors (38). Therefore, we undertook an open-label, first-in-human study (Clinicaltrials.gov identifier: NCT01781429) of oral ulixertinib to identify both the maximum tolerated dose (MTD) and the recommended phase II dose (RP2D). Study aims also included assessment of the pharmacokinetic and pharmacodynamic properties of ulixertinib as well as prelimi-nary efficacy in patients with genetic aberrations in BRAF, both at V600 and non-V600 positions, NRAS, and MEK.

RESULTSPatient Characteristics

Between April 4, 2013, and March 6, 2017, a total of 135 patients at 12 sites were consented and enrolled into this study; 27 patients were enrolled in the dose-escalation por-

tion and 108 patients enrolled in the cohort expansion por-tion (Fig. 1). All patients received at least one dose of study drug. Baseline demographics and disease characteristics are presented in Table 1. The median patient age across the study was 62 years. Fifty-two percent (14/27) and 64% (69/108) of patients were male, and 59% (16/27) and 68% (73/108) had an Eastern Cooperative Oncology Group performance status (ECOG PS) of 1 for the dose-escalation and cohort expansion phases of the study, respectively. Patients who had previ-ously received BRAF and/or MEK therapy represented 41% (11/27) of those enrolled in dose escalation and 19% (21/108) in cohort expansion, or 24% (32/135) overall. Furthermore, 51% (69/135) of patients had received prior immunotherapy. Elevated lactate dehydrogenase (LDH) was present in 46% (43/93) of patients evaluated in screening.

In cohort expansion, 108 patients were enrolled to six cohorts: patients without prior MAPK-targeted therapy who had BRAF-mutant colorectal (17 enrolled/11 evaluable), lung (16/12), or other cancers (24/21), NRAS-mutant melanoma (22/18), or any tumor type with a MEK mutation (8/4), and patients with melanoma who had received prior BRAF and/or MEK inhibitor treatment and who were refractory to, intolerant of, or progressed on these treatments (21/15). A variety of specific BRAF and NRAS mutations were included, as were a number of different tumor types (Supplementary Table S1). Collectively, 91 patients with tumors harboring mutations in BRAF, 24 with NRAS, 9 with MEK, 5 with no mutation identified, and 6 with other mutations (5 KRAS and 1 GNAS) were enrolled.

Dose Escalation, Dose-Limiting Toxicities, MTD, and RP2D

Per protocol, 5 single-patient cohorts (from 10 through 150 mg twice daily) proceeded without evidence of a dose-limiting toxicity (DLT). The 300-mg twice daily cohort was expanded to more fully characterize ulixertinib exposures. One of 6 patients given 600 mg twice daily experienced a DLT of grade 3 rash. The 900-mg twice daily dose exceeded the MTD, with 1 patient experiencing grade 3 pruritus, grade 3 elevated aspartate aminotransferase, and grade 3 elevated alanine aminotransferase, and another patient experiencing grade 3 diarrhea, grade 3 vomiting, grade 3 dehydration, and grade 3 elevated creatinine (Supple-mentary Table S2). The subsequent intermediate dose of 750 mg twice daily also exceeded the MTD, with DLTs of

Figure 1.  Study schema. An acceler-ated dose-escalation study design was used to investigate doses from 10 to 900 mg, twice daily (b.i.d.), followed by expansion cohorts initially receiving the preliminary recommended phase II dose (RP2D) of 600 mg, twice daily.

Oral ulixertinib b.i.d. (mg), 21-day cycle

10 20 40 75

150 300 750900600

BRAF-mutated colorectal cancer; naïve to priorBRAFi/MEKi therapy

BRAF-mutated non–small cell lung cancer; naïveto prior BRAFi/MEKi therapy

BRAF-mutated melanoma; refractory/progressed on BRAF/MEK inhibitors

BRAF-mutated solid tumors; naïve to priorBRAFi/MEKi therapy

NRAS-mutated melanoma; naïve to priorBRAFi/MEKi therapy

MEK-mutated solid tumors; naïve to priorBRAFi/MEKi therapy

Cancer Research. on December 17, 2020. © 2018 American Association forcancerdiscovery.aacrjournals.org Downloaded from

Published OnlineFirst December 15, 2017; DOI: 10.1158/2159-8290.CD-17-1119

Page 4: Two diseases, same person: moving towards a combined HIV and … · 70% and HIV prevalence among persons with presumptive TB (i.e. patients with TB symptoms but who may have a different

Phase I Trial of Ulixertinib, an Oral ERK 1/2 Inhibitor RESEARCH ARTICLE

february 2018 CANCER DISCOVERY | 187

Table 1.  Clinical characteristics of patients at baseline, including cancer types, prior therapies, and enrollment

Baseline characteristic All patients ( N = 135)Age Median (range), years 62 (21–85) ≥65 year 63 (47)

Sex, n (%) Male 83 (61) Female 52 (39)ECOG performance status, n (%) 0 45 (33) 1 90 (67)

Prior immune therapy, n (%) Yes 69 (51) No 66 (49)

Prior BRAFi/MEKi therapy, n (%) Yes 32 (24) No 103 (76)

Pretreatment LDH, n (%) Elevated 43 (32) Not elevated 50 (37) Not done 42 (31)

Body mass index Median (range), kg/m 2 26.83 (14.6–148.2)

Primary cancer type, n (%) Melanoma 53 (39) Colorectal 26 (19) Non–small cell lung 19 (14) Papillary thyroid 6 (4) Glioblastoma 4 (3) Prostate 3 (2) Small intestine 3 (2) Other a 21 (16)Enrollment, n (%) Dose escalation 27 (20)  BRAF colorectal cohort 17 (13)  BRAF non–small cell lung cohort 16 (12)  BRAF melanoma cohort 21 (16)  BRAF other cancer cohort 24 (18)  NRAS melanoma cohort 22 (16)  MEK cancer cohort 8 (6)

NOTE. Data are presented as N (%) unless indicated otherwise. a Includes adenoid cystic, angiosarcoma, appendiceal, cecum, cholan-giocarcinoma, gallbladder, gastrointestinal stromal tumor, mediastinal non-seminomatous germ cell tumor, mesothelioma, ovarian, pancreatic, salivary duct, small cell lung, squamous cell, thyroid, urachal, and vaginal.

grade 3 rash and grade 2 diarrhea in 1 patient and grade 2 hypotension, grade 2 anemia, and grade 1 elevated creatinine in another patient, which delayed cycle 2 dosing. Therefore, the MTD and RP2D were determined to be 600 mg twice daily.

Safety and Adverse Events Investigator-assessed treatment-related adverse events (AE)

of any grade were noted in 125 of 135 patients (93%) treated, whereas 105 of 115 patients (91%) treated at the RP2D had a treatment-related AE. Study wide, the most common treat-ment-related AEs were rash (76%, predominantly acneiform),

diarrhea (48%), fatigue (42%), and nausea (42%; Table 2 ). No patients experienced a grade 4 or 5 treatment-related AE. Most events were grade 1 to 2, with treatment-related grade 3 events noted in 56 of 135 patients (41%). The most common grade 3 treatment-related events were rash [17% of patients, includ-ing maculopapular ( n = 13), rash ( n = 5), dermatitis acneiform ( n = 4), and erythematous ( n = 1)], diarrhea (7%), anemia (4%), and fatigue (4%). AEs regardless of attribution leading to treatment interruptions occurred in 23 of 27 (85%) patients in dose escalation and 70 of 108 (65%) patients in cohort expansion, with gastrointestinal, and skin and subcutaneous disorders accounting for 20% and 15% of all dose interrup-tions, respectively. Median dose intensity for patients treated at RP2D was 89%. AEs leading to discontinuation regardless of attribution occurred in 26 of 135 (19%) patients, 3 in dose escalation (75, 300, and 900 mg twice daily) and 23 in cohort expansion. Twenty-fi ve patients experienced a total of 38 treatment-related serious AEs (SAE); the only events occur-ring in multiple patients were diarrhea ( n = 7), dehydration ( n = 4), acute renal failure, anemia, increased blood creatinine, maculo-papular rash, nausea, and vomiting ( n = 2 each).

Pharmacokinetics and Pharmacodynamics Pharmacokinetic analyses of ulixertinib following a single

dose and after achieving steady state in dose escalation are summarized in Fig. 2A and B . Generally, orally administered ulixertinib (taken without food) was slowly absorbed, reach-ing maximum concentration (C max ) at approximately 2 to 4 hours, and then declining slowly thereafter. Plasma drug concentrations were measured as a function of time through a single dosing period (12 hours). As such, it was not possible to calculate an effective or terminal phase elimination rate. Ulixertinib pharmacokinetics were linear and dose propor-tional in terms of both C max (Supplementary Table S3) and area under the curve (AUC) when administered up to 600 mg twice daily on day 1 and at steady state ( Fig. 2C and D , respec-tively). A further increase in exposure was not observed as the dose increased from 600 to 900 mg twice daily, although only a limited number of patients were treated at the higher dose levels. Minimal plasma accumulation of ulixertinib and its metabolites was observed at steady state at the lower (<75 mg twice daily) dose levels, whereas accumulation ranged from approximately 1.3- to 4.0-fold for the higher dose levels. The degree of inter-patient variability in plasma exposure to ulixertinib and its metabolites was moderate and considered clinically manage-able. Urinary excretion of ulixertinib on day 1 and at steady state was negligible (<0.2% of the dose) and not dose-related within this very low percentage range. Individual renal clear-ance values ranged from 0.128 to 0.0895 L/hour (where n = 1 patient per dose level) and mean values ranged from 0.0149 to 0.0300 L/hour (where n ≥3 patients).

To confi rm on-target and pathway inhibition by ulixertinib, we examined RSK1 phosphorylation as a target biomarker in patients’ whole-blood samples following oral dosing (assay provided in Methods). Samples collected from ulixertinib-treated patients displayed concentration-dependent inhibition of PMA-stimulated ERK activity ( Fig. 2E ), ranging from 0% ERK inhibition for patients dosed at 10 mg twice daily to 93% ± 8% ERK inhibition with dosing at 900 mg twice daily, when measured at trough. Near-complete (86% ± 12%) inhibition

Cancer Research. on December 17, 2020. © 2018 American Association forcancerdiscovery.aacrjournals.org Downloaded from

Published OnlineFirst December 15, 2017; DOI: 10.1158/2159-8290.CD-17-1119

Page 5: Two diseases, same person: moving towards a combined HIV and … · 70% and HIV prevalence among persons with presumptive TB (i.e. patients with TB symptoms but who may have a different

Sullivan et al.RESEARCH ARTICLE

188 | CANCER DISCOVERY february 2018 www.aacrjournals.org

Table 2.  Patients with AEs that occurred in ê10% (possibly related or related) including combined rash events and combined ocular events

<300 mg b.i.d. ( n = 5) 300 mg b.i.d. ( n = 4) 600 mg ( n = 115) >600 mg b.i.d. ( n = 11)

Adverse event, n (%) Grade 1/2 Grade 3 Grade 1/2 Grade 3 Grade 1/2 Grade 3 Grade 1/2 Grade 3 Total ( N = 135)Combined rash a 3 (60) 0 (0) 3 (75) 0 (0) 65 (56) 22 (19) 8 (72) 1 (9) 102 (76)

Diarrhea 5 (100) 0 (0) 1 (25) 0 (0) 44 (38) 7 (6) 5 (45) 3 (27) 65 (48)

Fatigue 3 (60) 0 (0) 1 (25) 0 (0) 43 (37) 3 (3) 5 (45) 2 (18) 57 (42)

Nausea 3 (60) 0 (0) 2 (50) 0 (0) 44 (38) 2 (2) 6 (54) 0 (0) 57 (42)

Decreased appetite 0 (0) 0 (0) 0 (0) 0 (0) 28 (24) 0 (0) 6 (54) 0 (0) 34 (25)

Pruritus 0 (0) 0 (0) 1 (25) 0 (0) 27 (23) 1 (<1) 4 (36) 0 (0) 33 (24)

Vomiting 0 (0) 0 (0) 2 (50) 0 (0) 18 (16) 1 (<1) 4 (36) 1 (9) 26 (19)

Combined ocular events b

1 (20) 0 (0) 0 (0) 0 (0) 14 (12) 1 (<1) 2 (18) 0 (0) 18 (13)

Edema peripheral 1 (20) 0 (0) 0 (0) 0 (0) 12 (10) 1 (<1) 1 (9) 0 (0) 15 (11)

Anemia 0 (0) 1 (20) 0 (0) 0 (0) 6 (5) 5 (4) 0 (0) 3 (27) 15 (11)

Dehydration 0 (0) 0 (0) 0 (0) 0 (0) 9 (8) 1 (<1) 1 (9) 2 (18) 13 (10)

Alopecia 1 (20) 0 (0) 0 (0) 0 (0) 10 (9) 0 (0) 2 (18) 0 (0) 13 (10)

Abbreviation: b.i.d., twice daily. a “Combined rash” includes preferred terms of dermatitis acneiform (42), acne (1), skin exfoliation (2), and any term containing rash (81). b “Combined ocular events” includes preferred terms of halo vision (1), photophobia (2), retinal detachment (1), retinal vein occlusion (1), retinopathy (1), vision blurred (6), visual impairment (10), and vitreous fl oaters (1). Note that retinal vein occlusion event (grade 3) occurred after >10 months on study and resolved with drug cessation.

of ERK activity was observed throughout the entire dosing period at RP2D. Ulixertinib exposures in cohort-expansion patients dosed at the RP2D were C max 1.15 and 2.12 μg/mL and AUC 0-12 8.07 and 19.93 μg*h/mL after the fi rst dose and at steady state, respectively ( Fig. 2F ).

Antitumor Effects Tumor response to ulixertinib was assessed in 25 and

81 evaluable patients from the dose-escalation and expan-sion cohorts, respectively, using Response Evaluation Criteria in Solid Tumors version 1.1 (RECIST v1.1). Per protocol, evaluable patients were defi ned as those who completed two cycles of treatment. Although no patient achieved a complete response, 14 partial responses were observed in 101 evaluable patients who were dosed at 600 mg twice daily or greater (3 in dose escalation and 11 in cohort expansion).

Dose-Escalation Cohorts In dose escalation, 3 of 25 (12%) evaluable patients (all with

melanoma harboring BRAF V600 mutations) achieved partial responses (PR). These 3 patients, who were BRAF/MEK ther-apy naïve, intolerant, or refractory, had response durations of 4.2, 12.4, and 24.9 months, respectively ( Fig. 3A and B ). Fig-ure 3C shows computed tomography (CT) scans of one of the responders, who had progressed on prior vemurafenib and subsequent dabrafenib treatment and maintained a PR for 24.9 months. Noteworthy, this patient’s PR was fi rst observed after 13.5 months of treatment, whereas total time on study exceeded 38.4 months (ongoing at data cutoff).

Additionally, 6 patients had stable disease for more than 6 months. Figure 3B depicts the time to PR and the duration of

response in this study population. One patient with bronchi-oloalveolar non–small cell lung cancer (not enough tissue for molecular profi ling) was on treatment for >26.2 months with stable disease. Twenty-six of 27 patients (96%) discontinued treatment due to progressive disease (85%, 23/27) or other reasons (11%, 3/27; 1 drug-related and 2 unrelated AEs). The mean duration of ulixertinib treatment before discontinua-tion was 6.6 months.

Dose-Expansion Cohorts In dose expansion, the tumor response and duration on

study for each cohort are depicted in Fig. 4A and B , respectively. PRs were seen in 11 of 81 (14%) evaluable patients, including 3 of 18 with NRAS -mutant melanoma, 3 of 12 with BRAF -mutant lung cancer (2 with V600E and 1 with L597Q), 1 of 15 with BRAF/MEK inhibitor–refractory BRAF V600E–mutant melanoma, and 4 of 21 with other BRAF -mutant cancers. These include one each of BRAF L485W gallbladder cancer ( Fig. 5A ), BRAF V600E glioblastoma multiforme ( Fig. 5B ), BRAF G469A head and neck cancer, and BRAF G469A small-bowel cancer. Of these patients, two of the responses lasted greater than 4.9 months. The maximal tumor responses for patients with BRAF non-V600 mutations ( n = 28) are shown in Fig. 4C and are classifi ed by their kinase activity ( 12, 40 ). Of note, central nerv-ous system (CNS) responses were seen in a patient with BRAF V600E–mutant lung cancer with metastases, and another with BRAF V600E–mutant glioblastoma mulitforme.

Based on the preclinical data, it was expected that ulixerti-nib would have activity in patients with melanoma harboring mutations in the MAPK pathway ( 39 ). In all (including dose escalation and expansion), 53 patients with melanoma were

Cancer Research. on December 17, 2020. © 2018 American Association forcancerdiscovery.aacrjournals.org Downloaded from

Published OnlineFirst December 15, 2017; DOI: 10.1158/2159-8290.CD-17-1119

Page 6: Two diseases, same person: moving towards a combined HIV and … · 70% and HIV prevalence among persons with presumptive TB (i.e. patients with TB symptoms but who may have a different

Phase I Trial of Ulixertinib, an Oral ERK 1/2 Inhibitor RESEARCH ARTICLE

february 2018 CANCER DISCOVERY | 189

0 2 4 6 8 10 12

900 mg, b.i.d.

750 mg, b.i.d.

600 mg, b.i.d.

300 mg, b.i.d.

150 mg, b.i.d.

75 mg, b.i.d.

40 mg, b.i.d.

20 mg, b.i.d.

10 mg, b.i.d.1

10

100

1,000

10,000

0 2 4 6 8 10 12

Pla

sma

ulix

ertin

ib (

ng/m

L)

0

10

20

30

40

50

0 100 200 300 400 500 600 700800 900

Pla

sma

BV

D-5

23

(ug*

hr/m

L)

Dose Level (mg, BID)0 100 200 300 400 500 600 700 800 9000

10

20

30

40

50

0 100 200 300 400 500 600 700 800 900

DV

B amsal

P-5

23

(ug*

hr/m

L)

Dose Level (mg, BID)

0

10

20

30

40

50

0 100 200 300 400 500 600 700 800 900

0

0.5

1

1.5

2

2.5

3

3.5

0 2 4 6 8 10 12

Pla

sma

ulix

ertin

ib (

µg/m

L)

Time (hours)

Day 1 Steady state

Time (hours)

Pla

sma

ulix

ertin

ib (

µg/m

L)

pRS

K/total R

SK

(% B

aseline)

Dose (mg, b.i.d.)

Dose level (mg, b.i.d.)

0

25

50

75

100

0

1

2

3

0 150 300 450 600 750 900

Ulix

ertin

ib A

UC

(0–l

ast)

(µg/

h/m

L)

A

C

E F

D

B

Figure 2.  Pharmacokinetics and pharmacodynamics of ulixertinib. Plasma concentrations of ulixertinib as a function of time and dose level following dosing on day 1 (A) and at steady state (B). AUC as a function of dose level following dosing on day 1 (C) and at steady state (D). The data for dose levels 10 to 150 mg twice daily (b.i.d.) represent a single patient at each dose level. Plasma levels and pharmacodynamic effects of ulixertinib are shown as a function of the dose level (E). Ulixertinib plasma levels from patients dosed with 600 mg/kg, twice daily, are shown at day 1 and steady state (F).

treated with ulixertinib, and 40 were eligible for response evaluation per RECIST v1.1. In 19 such patients with BRAF-mutant melanoma previously treated with a BRAF and/or MEK inhibitor, 3 (15%) achieved a PR, 6 had stable disease, and 10 had progressive disease as a best response. In the patients with a PR, the time from last MAPK-targeted therapy was 21, 26, and 169 days, respectively. In patients with stable disease, this number ranged from 19 to 713 days; however, all but one commenced therapy within 6 weeks of the last dose of these targeted therapies. Seventeen patients with NRAS-mutated melanoma were evaluable for response. Three patients (18%) achieved a PR, 6 had stable disease, and 8 had

disease progression as best response. Additionally, 3 other patients with melanoma harboring BRAF mutations, who had not received prior targeted therapy, were treated. One of 2 patients with a BRAF V600 mutation responded, and the 1 patient with a BRAF fusion had stable disease.

DISCUSSIONWe report results from a first-in-human study evaluating

the safety, pharmacokinetics, pharmacodynamics, and pre-liminary efficacy of ulixertinib in 135 patients with advanced solid tumors. In the dose-escalation portion of this study,

Cancer Research. on December 17, 2020. © 2018 American Association forcancerdiscovery.aacrjournals.org Downloaded from

Published OnlineFirst December 15, 2017; DOI: 10.1158/2159-8290.CD-17-1119

Page 7: Two diseases, same person: moving towards a combined HIV and … · 70% and HIV prevalence among persons with presumptive TB (i.e. patients with TB symptoms but who may have a different

Sullivan et al.RESEARCH ARTICLE

190 | CANCER DISCOVERY february 2018 www.aacrjournals.org

Figure 3.  Dose-escalation patient response. Individual patient’s target lesion response (A) and time on study (B) are shown as a function of initial dose level. C, A representative sustained partial tumor response in a melanoma patient that was refractory to prior BRAF inhibitor therapy. Horizontal red line in A depicts RECIST v1.1 partial response threshold. b.i.d., twice daily.

A

B

C

60.00

40.00

20.00

0.00

Targ

et le

sion

% c

hang

e fr

om b

asel

ine

−20.00

Starting dose

Starting dose

−40.00 10 mg b.i.d.

20 mg b.i.d.

10 mg b.i.d.

20 mg b.i.d.40 mg b.i.d.75 mg b.i.d.150 mg b.i.d.

300 mg b.i.d.600 mg b.i.d.750 mg b.i.d.900 mg b.i.d.

Partial response

40 mg b.i.d.

75 mg b.i.d.

150 mg b.i.d.300 mg b.i.d.

600 mg b.i.d.750 mg b.i.d.900 mg b.i.d.

0 50 100 150 200 250 300

Days on study

350 400 450 500 650 900 1,150

−60.00

−80.00

−100.00

PretreatmentC4D1

−49.6%C8D1

−65.7%C48D1−79.6%

Cancer Research. on December 17, 2020. © 2018 American Association forcancerdiscovery.aacrjournals.org Downloaded from

Published OnlineFirst December 15, 2017; DOI: 10.1158/2159-8290.CD-17-1119

Page 8: Two diseases, same person: moving towards a combined HIV and … · 70% and HIV prevalence among persons with presumptive TB (i.e. patients with TB symptoms but who may have a different

Phase I Trial of Ulixertinib, an Oral ERK 1/2 Inhibitor RESEARCH ARTICLE

february 2018 CANCER DISCOVERY | 191

Figure 4.  Cohort expansion patient response. Target lesion responses (A) and time on study (B), grouped by cohort, are shown for each evaluable patient ini-tially dosed with 600 mg of ulixertinib twice daily in the expansion phase of the study. Specific genetic mutations are also indicated (A, B). C, Tumor response data for patients with atypical (non-V600) BRAF mutations, with specific mutations indicated. Data are further discriminated by color based on the literature-reported MAPK pathway activity, as indicated by pERK levels. CRC, colorectal cancer; NSCLC, non–small cell lung cancer.

BRAF NRAS MEK

CRC

60.00

40.00

20.00

40.00

D594G

D594N

D594N

G469A

G469A

G469A

G466V

F247L

T599

dup

K601E

D594G

D594G

K601E

L597

R

D594N

K601E

D594

D594G

D594G

G469V

L597

Q

D594N

G469A

T599

dup

L597

Q

L485

W

G469A

NFIC fu

sion

30.00

20.00

10.00

0.00

–10.00

–20.00

–30.00

–40.00

–50.00

–60.00

–70.00

–80.00

–90.00

–100.00

0.00

–20.00

–40.00

–60.00

–80.00

–100.00

Tar

get l

esio

n %

cha

nge

from

bas

elin

eT

arge

t les

ion

% c

hang

e fr

om b

asel

ine

NSCLC Melanoma

0 50 100 150 200 250 300

High pERKLow pERKUnknown

350 400 450

Others Melanoma Any

Atypical BRAFBRAF V600MAP2K1NRAS G13NRAS Q61NRAS unspecified

Atypical BRAF

BRAF V600

MAP2K1

NRAS G13

NRAS Q61

NRAS unspecified

BR

AF

NR

AS

ME

K

Days on study

CR

CN

SC

LCM

elan

oma

Oth

ers

Mel

anom

aA

ny

Not

ass

esse

d

A

B

C

Cancer Research. on December 17, 2020. © 2018 American Association forcancerdiscovery.aacrjournals.org Downloaded from

Published OnlineFirst December 15, 2017; DOI: 10.1158/2159-8290.CD-17-1119

Page 9: Two diseases, same person: moving towards a combined HIV and … · 70% and HIV prevalence among persons with presumptive TB (i.e. patients with TB symptoms but who may have a different

Sullivan et al.RESEARCH ARTICLE

192 | CANCER DISCOVERY february 2018 www.aacrjournals.org

Figure 5.  Representative patient responses to ulixertinib. Longitudinal radiographic scans from a subset of patients who responded to ulixertinib are shown. A, A patient with gallblad-der adenocarcinoma with a BRAF L485W mutation who experienced partial response in two lesions (green circles) over 12 weeks. B, A patient with glioblastoma multiforme with a BRAF V600E mutation who experienced a 64% reduction of their tumor (green circles) after 10 cycles of treatment with ulixertinib.

Baseline

A

B

6 Weeks posttreatment

12 Weeks posttreatment

Lesi

on 1

Lesi

on 2

Baseline:progression

6 Weeks posttreatment

21 Weeks posttreatment

30 Weeks posttreatment

Priormeasurement

oral treatment with ulixertinib resulted in both radiographic responses by RECIST v1.1 (3 PRs) and prolonged disease stabilization in some patients, many with tumor alterations consistent with MAPK activation (BRAF, KRAS, NRAS). Drug exposures increased linearly with increasing doses up to 600 mg twice daily, which provided near-complete 24/7 inhi-bition of ERK substrate (RSK1) phosphorylation in an ex vivo whole-blood assay. Furthermore, toxicities associated with ulixertinib were consistent with preclinical models and were manageable when administered up to its MTD and RP2D, determined to be 600 mg twice daily.

Ulixertinib was successfully administered in six cohorts of patients with NRAS, BRAF, and MEK mutations at the RP2D, which demonstrated unique and encouraging clinical activity. Tumor regression and/or stabilization of disease was seen in every dose cohort, and partial responses were seen in patients with a variety of solid-tumor malignancies with mutations in BRAF V600E/K, non-V600 BRAF, and NRAS. In particular, non-V600 BRAF mutations, including L485W, L597Q, and G469A across a variety of solid tumors, were shown to be clinically actionable for the first time, with dura-ble objective responses. This study provides the first clini-cal evidence that dimer-dependent atypical BRAF non-V600 mutations may be actionable by downstream ERK inhibition, highlighting an important new therapeutic target for future drug development in solid tumors. Furthermore, the CNS activity of ulixertinib was clinically demonstrated by the objective responses achieved in glioblastoma multiforme and lung cancer with brain metastases.

Ulixertinib was generally well tolerated, with manageable and reversible toxicity. The most common AEs were rash (most commonly acneiform), fatigue, and gastrointestinal AEs, including nausea, vomiting, and diarrhea. The safety profile of ulixertinib is consistent with its selective inhibition of the MAPK pathway; the AE profile overlaps considerably with MEK inhibitor experience (41). However, toxicities asso-

ciated with any targeted therapy may include dependence on both the specific mechanism and the degree of target inhibi-tion, as well as any off-target effects.

Durable responses by RAF and MEK inhibitors are often limited by intrinsic and eventual acquired resistance, with a common feature often involving reactivation of the ERK pathway (25–31, 38). Thus, ERK inhibition with ulixertinib alone or in combination with other MAPK signaling path-way inhibitors may have the potential to delay the develop-ment of resistance to existing therapies and to benefit a broader patient population (42). The ability of ERK inhibi-tors, including ulixertinib, to retain their potency in BRAF- and MEK-resistant cell lines provides preclinical evidence for their use in patients with acquired resistance to standard of care (BRAF/MEK inhibitor combination therapy; refs. 34, 35, 39). Importantly, in this study, 9 of 19 patients with BRAF-mutant melanoma previously treated with MAPK inhibitor therapy had either a PR or stable disease, including a patient with a PR while receiving ulixertinib whose cancer had pro-gressed after experiencing stable disease when treated initially with a BRAF inhibitor (vemurafenib) and subsequently with dabrafenib. This patient remained on study for a total of 38.4 months as of the cutoff date of this publication. Based in part on the antitumor effects observed in this patient, the FDA has designated as a Fast Track development program the investigation of ulixertinib for the treatment of patients with unresectable or metastatic BRAF V600 mutation–positive melanoma that is refractory to or has progressed following treatment with a BRAF and/or MEK inhibitor(s). One poten-tial explanation for this activity in patients with BRAF-mutant melanoma previously treated with MAPK pathway–targeted therapy is repopulation of the tumor following a break in treatment (43). However, in 2 of the 3 PRs and 5 of the 6 patients with stable disease, ulixertinib commenced within 6 weeks of the last BRAF and/or MEK inhibitor dose, with the majority treated within 4 weeks.

Cancer Research. on December 17, 2020. © 2018 American Association forcancerdiscovery.aacrjournals.org Downloaded from

Published OnlineFirst December 15, 2017; DOI: 10.1158/2159-8290.CD-17-1119

Page 10: Two diseases, same person: moving towards a combined HIV and … · 70% and HIV prevalence among persons with presumptive TB (i.e. patients with TB symptoms but who may have a different

Phase I Trial of Ulixertinib, an Oral ERK 1/2 Inhibitor RESEARCH ARTICLE

february 2018 CANCER DISCOVERY | 193

In summary, we report initial data from the phase I study evaluating ulixertinib, a first-in-class ERK inhibitor, as a treat-ment for patients with advanced cancers. Continuous, twice-daily oral treatment with ulixertinib resulted in antitumor effects in subsets of patients with a variety of solid-tumor types, including patients either naïve to or having progressed on available MAPK pathway–targeted therapies. Ulixertinib generally was well tolerated in this population of patients with advanced cancer, and toxicities were manageable; the MTD and RP2D were 600 mg twice daily. Ulixertinib exposures increased linearly up to the RP2D, and robust pharmacodynamic effects were evident at this dose level. The preliminary efficacy shown in a variety of molecularly defined cohorts, hallmarked by MAPK activating alterations, supports the ongoing develop-ment of ulixertinib as a single agent as well as in combination.

METHODSPatients

Between April 4, 2013, and March 6, 2017, a total of 135 patients at 12 sites were consented and enrolled into the study, after local Insti-tutional Review Board approval. All participants provided informed consent prior to initiation of any study procedures. Patients ages ≥18 years were eligible for participation if they had noncurable, histologically confirmed metastatic or advanced-stage malignant tumors; an ECOG PS of 0 or 1; adequate renal, hepatic, bone mar-row, and cardiac function; and a life expectancy ≥3 months. Patients may have received up to two prior lines of chemotherapy for their metastatic disease. Exclusion criteria were known uncontrolled brain metastases; gastrointestinal conditions that could impair absorption of study medication; history or current evidence/risk of retinal vein occlusion or central serous retinopathy; and concurrent therapy with drugs known to be strong inhibitors of CYP1A2, CYP2D6, and CYP3A4, or strong inducers of CYP3A4.

Patients who received at least one dose of ulixertinib were included in the analysis. We used SAS (version 9.3) to support this study. The data cutoff was March 6, 2017. This study is registered with ClinicalTrials.gov (NCT01781429).

Study Design and ObjectivesThis was an open-label, phase I study to assess the safety, pharma-

cokinetics, and pharmacodynamics of escalating doses of ulixertinib in a capsule formulation in patients with advanced malignancies. The dosing regimen combined both accelerated titration and stand-ard cohort 3 + 3 dose-escalation schema, which were used jointly to identify the MTD and RP2D of ulixertinib in patients with advanced solid tumors. One to 6 patients per treatment cohort were assigned to receive sequentially higher oral doses of ulixertinib administered twice daily (12-hour intervals) continuously in 21-day cycles at the following doses: 10 mg (n = 1); 20 mg (n = 1); 40 mg (n = 1); 75 mg (n = 1); 150 mg (n = 1); 300 mg (n = 4); 600 mg (n = 7); 900 mg (n = 7); and 750 mg (n = 4). In the cohort-expansion phase, patients were enrolled to one of six cohorts until at least 15 patients per cohort were expected to be evaluable for response to therapy. The six cohorts were defined as patients without prior MAPK targeted therapy that had BRAF-mutant colorectal (17 enrolled/11 evaluable), lung (16/12), or other cancers (24/21), NRAS-mutant melanoma (22/18), or any tumor type with a MEK mutation (8/4), and patients with mela-noma who had prior BRAF and/or MEK inhibitor treatment (21/15). Notably, the cohort of patients with MEK mutations was closed after enrollment of only 8 patients, due to slow accrual.

Patients received ulixertinib until disease progression, unaccepta-ble toxicity, or a clinical observation satisfying another withdrawal

criterion. Dose escalations occurred in up to 100% increments in single-patient cohorts until 1 patient experienced at least a grade 2 toxicity (excluding alopecia or diarrhea). Cohorts were then expanded to at least 3 patients each, and subsequent dose-escalation incre-ments were reduced from up to 100% to a maximum of 50%. When at least 1 patient in a 3-patient cohort experienced a DLT, up to 3 additional patients were treated at this dose level. When more than 1 DLT occurred in ≤6 patients, this dose level was defined as the non-tolerated dose, and dose escalation was stopped. Intrapatient dose escalation was allowed, provided the patients receiving the highest current dose had been observed for at least 3 weeks and dose-limiting AEs were reported in fewer than 2 of 6 patients assigned to that dose. Patients experiencing DLTs or unacceptable toxicity had their treatment interrupted until the toxicity returned to grade 1 or lower. Resumption of ulixertinib treatment was then initiated at the next lower dose level tested or at a 20% to 30% dose decrease, aligning with capsule strength.

The primary objective of the study was to define the safety and tolerability of ulixertinib by determining the DLTs, the MTD, and the RP2D. The secondary objectives included the determination of the pharmacokinetic profile of ulixertinib and the investigation of any preliminary clinical effects on tumor response, as assessed by physical or radiologic examination using RECIST v1.1. The explora-tory objectives included evaluation of pharmacodynamic marker (biomarker) measures.

MTD, DLT, and RP2DMTD was defined as the highest dose cohort at which ≤33% of

patients experienced ulixertinib-related DLTs in the first 21 days of treatment. DLT was defined as a ulixertinib-related toxicity in the first 21 days of treatment that resulted in a grade 4 or higher hematologic toxicity for >1 day; grade 3 hematologic toxicity with complications (e.g., thrombocytopenia with bleeding); grade 3 or higher nonhematologic toxicity, except untreated nausea, vomiting, constipation, pain, and rash (these become DLTs if the AE persisted despite adequate treatment); or a treatment interruption exceeding 3 days in cycle 1 (or the inability to be in cycle 2 for >7 days) due to ulixertinib-related toxicity.

The RP2D could be as high as the MTD and was determined in dis-cussion with the clinical investigators, medical monitor, and sponsor. Observations related to pharmacokinetics, pharmacodynamics, and any cumulative toxicity observed after multiple cycles were included in the rationale supporting the RP2D.

Safety AssessmentsPatients who received ulixertinib and experienced any untoward

medical occurrence had their AE defined as per the MedDRA coding dictionary, regardless of causal relationship with test article. The AEs were graded according to the National Cancer Institute Com-mon Terminology Criteria for Adverse Events, Grading Scale, version 4.03. Investigators assessed the relationship of AEs to study drug as either unrelated, possibly related, or related, and followed up until event resolution or stabilization or the AE was judged to no longer be clinically significant. An SAE was defined as any untoward medi-cal occurrence that resulted in death, was life-threatening, required inpatient hospitalization or prolongation of existing hospitalization, or resulted in persistent or significant disability/incapacity or a con-genital anomaly/birth defect.

Safety evaluations were conducted at baseline, on days 8, 15, 22, 29, 36, and 43, and, in patients who continued treatment, every 3 weeks or if clinically indicated thereafter. Each evaluation included a physical examination and clinical laboratory studies. Electrocar-diograms were repeated if clinically significant and at the discretion of the investigator. Holter monitoring (12 ± 2 hours) was performed in a subset of patients in cycle 1, at day 1 and day 15 (PK sampling

Cancer Research. on December 17, 2020. © 2018 American Association forcancerdiscovery.aacrjournals.org Downloaded from

Published OnlineFirst December 15, 2017; DOI: 10.1158/2159-8290.CD-17-1119

Page 11: Two diseases, same person: moving towards a combined HIV and … · 70% and HIV prevalence among persons with presumptive TB (i.e. patients with TB symptoms but who may have a different

Sullivan et al.RESEARCH ARTICLE

194 | CANCER DISCOVERY february 2018 www.aacrjournals.org

days) and Holter ECG analyses were conducted by BioClinica. An ophthalmologic assessment was also conducted at screening, at the end of study, and at other visits by an ophthalmologist if clinically indicated.

Pharmacokinetic AnalysisThe pharmacokinetic population consisted of patients who received

at least 1 dose of ulixertinib and had evaluable pharmacokinetic data for plasma and/or urine. Blood samples were collected prior to dosing, and then at 0.5 (± 5 minutes), 1 (± 5 minutes), 2 (± 10 minutes), 4 (± 10 minutes), 6 (± 10 minutes), 8 (± 10 minutes), and 12 (±2 hours) hours on day 1 (visit 2; baseline/initiation of treatment) and day 15 (visit 4; at steady state). On day 22, prior to dose administration, a final blood sample was collected for pharmacokinetic analyses. Urine samples were collected pre-dose and at the 1- to 6-hour and 6- to 12- (± 2) hour intervals post-dose on days 1 and 15. Plasma and urine samples were analyzed for ulixertinib and metabolites using validated LC/MS-MS methods. Standard pharmacokinetic parameters were obtained using Phoenix WinNonlin (Pharsight) with a noncompartmental method. Relationship between dose and exposure was calculated using stand-ard least-squares regression analysis.

Pharmacodynamic Confirmation of Target Inhibition by Ulixertinib

ERK inhibition by ulixertinib was determined by measuring pRSK/RSK as a target biomarker in human whole-blood samples obtained from patients who had received ulixertinib during the phase I study. To establish a ulixertinib-dependent RSK1-phospho-rylation calibration curve, healthy donor blood was treated with serial dilutions of ulixertinib (DMSO control) for 2 to 3 hours fol-lowed by stimulation with 100 nmol/L PMA for 20 minutes at room temperature. Peripheral blood mononuclear cells were isolated, lysed, and flash-frozen prior to measurement of pRSK and total RSK by ELISA (PathScan).

A plot of the pRSK/RSK ratio as a function of ulixertinib con-centration was used as a standard curve for determination of ERK activity. Maximum (100%) inhibition was defined as the pRSK/RSK value obtained in the presence of 10 μmol/L ulixertinib: Baseline inhibition was defined as the pRSK/RSK value obtained in untreated and unstimulated blood. The EC50 for ulixertinib was determined to be ∼200 ng/mL.

Patient samples were evaluated using this methodology, with each patient serving as their own control for maximal and minimal stimu-lation. Pre- and post-ulixertinib treatment samples were collected at day 1 and steady state.

Antitumor ResponseTumor measurements based on physical examination occurred at

baseline and on the first day of each treatment cycle. CT and other assessments were made every 2 to 3 cycles. Findings were assessed in accordance with RECIST v1.1: Complete response was defined as disappearance of all target lesions; PR was defined as a ≥30% decrease in the sum of the longest diameters of target lesions, taking baseline measurements as reference; stable disease was defined as being of neither sufficient shrinkage to qualify for PR nor sufficient increase to qualify for progressive disease, taking as reference the baseline measurement. CT scans were performed per routine site protocols and assessed by site radiologists; no central read assessments were included in this analysis.

Disclosure of Potential Conflicts of InterestR.J. Sullivan reports receiving a commercial research grant from Merck

and is a consultant/advisory board member for Merck and Novartis. J.R. Infante is Vice President of Early Development at Johnson & Johnson

and is a consultant/advisory board member for BioMed Valley. F. Janku reports receiving commercial research grants from BioMed Valley Discoveries, Novartis, and Plexxikon, has ownership interest (including patents) in Trovagene, and is a consultant/advisory board member for Novartis. G.I. Shapiro reports receiving commercial research grants from Pfizer, Lilly, and Merck/EMD Serono, and is a consultant/advisory board member for Pfizer, Lilly, G1 Therapeu-tics, Roche, Vertex Pharmaceuticals, and Merck/EMD Serono. A.W. Tolcher is a consultant/advisory board member for Asana and Astex. A. Wang-Gillam is a consultant/advisory board member for Pfizer, Merrimack, Ipsen, Newlink, Jacobio, and Repugene. M. Sznol is a consultant/advisory board member for Novartis, Genentech/Roche, and Pierre-Fabre. R.D. Carvajal is a consultant/advisory board mem-ber for Bristol-Myers Squibb, Janssen, Iconic Therapeutics, Merck, Roche/Genentech, Aura Biosciences, Chimeron, and Rgenix. S.P. Patel has received honoraria from the speakers bureaus of Bristol-Myers Squibb and Merck, has ownership interest (including pat-ents) in Provectus, and is a consultant/advisory board member for Amgen, Castle Biosciences, Genentech, and Incyte. M. Varterasian is a consultant/advisory board member for BioMed Valley Discover-ies. D.M. Hyman reports receiving commercial research grants from AstraZeneca, Puma Biotechnology, and Loxo Oncology, and is a con-sultant/advisory board member for CytomX, Atara Biotherapeutics, Boehringer Ingelheim, Chugai, and AstraZeneca. B.T. Li is a consult-ant/advisory board member for Genentech. No potential conflicts of interest were disclosed by the other authors.

Authors’ ContributionsConception and design: R.J. Sullivan, J.R. Infante, K. Flaherty, G.A. DeCrescenzo, C.M. Emery, S. Saha, M. Varterasian, D.J. Welsch, D.M. HymanDevelopment of methodology: J.R. Infante, K. Flaherty, G.A. DeCrescenzo, S. Saha, M. Varterasian, D.J. Welsch, B.T. LiAcquisition of data (provided animals, acquired and man-aged patients, provided facilities, etc.): R.J. Sullivan, J.R. Infante, F. Janku, D.J.L. Wong, J.A. Sosman, V. Keedy, M.R. Patel, G.I. Shapiro, J.W. Mier, A.W. Tolcher, A. Wang-Gillam, M. Sznol, E. Buchbinder, R.D. Carvajal, A.M. Varghese, M.E. Lacouture, A. Ribas, S.P. Patel, C.M. Emery, A.L. Groover, D.J. Welsch, D.M. Hyman, B.T. LiAnalysis and interpretation of data (e.g., statistical analysis, biostatistics, computational analysis): R.J. Sullivan, J.R. Infante, F. Janku, D.J.L. Wong, M.R. Patel, A.W. Tolcher, K. Flaherty, A.M. Varghese, M.E. Lacouture, A. Ribas, G.A. DeCrescenzo, C.M. Emery, A.L. Groover, M. Varterasian, D.J. Welsch, B.T. LiWriting, review, and/or revision of the manuscript: R.J. Sullivan, J.R. Infante, F. Janku, D.J.L. Wong, J.A. Sosman, V. Keedy, M.R. Patel, G.I. Shapiro, A.W. Tolcher, A. Wang-Gillam, M. Sznol, K. Flaherty, E. Buchbinder, R.D. Carvajal, A.M. Varghese, M.E. Lacouture, A. Ribas, S.P. Patel, G.A. DeCrescenzo, C.M. Emery, A.L. Groover, S. Saha, M. Varterasian, D.J. Welsch, D.M. Hyman, B.T. LiAdministrative, technical, or material support (i.e., reporting or organizing data, constructing databases): R.J. Sullivan, J.R. Infante, M.E. Lacouture, S.P. Patel, C.M. Emery, A.L. Groover, S. Saha, D.J. Welsch, B.T. LiStudy supervision: R.J. Sullivan, J.R. Infante, V. Keedy, G.I. Shapiro, A.W. Tolcher, A. Wang-Gillam, M.E. Lacouture, S.P. Patel, S. Saha, M. Varterasian, D.J. Welsch, B.T. Li

AcknowledgmentsThe authors would like to acknowledge Heide Hope from Conflu-

ence for her work and contribution on the RSK-1 phosphorylation assay. This work was funded by BioMed Valley Discoveries, Inc.

Received October 8, 2017; revised November 6, 2017; accepted November 6, 2017; published OnlineFirst December 15, 2017.

Cancer Research. on December 17, 2020. © 2018 American Association forcancerdiscovery.aacrjournals.org Downloaded from

Published OnlineFirst December 15, 2017; DOI: 10.1158/2159-8290.CD-17-1119

Page 12: Two diseases, same person: moving towards a combined HIV and … · 70% and HIV prevalence among persons with presumptive TB (i.e. patients with TB symptoms but who may have a different

Phase I Trial of Ulixertinib, an Oral ERK 1/2 Inhibitor RESEARCH ARTICLE

february 2018 CANCER DISCOVERY | 195

REFEREnCES 1. Roskoski R Jr. ERK1/2 MAP kinases: structure, function, and regula-

tion. Pharmacol Res 2012;66:105–43. 2. Schubbert S, Shannon K, Bollag G. Hyperactive Ras in developmental

disorders and cancer. Nat Rev Cancer 2007;7:295–308. 3. Kanda M, Matthaei H, Wu J, Hong SM, Yu J, Borges M, et al. Presence

of somatic mutations in most early-stage pancreatic intraepithelial neoplasia. Gastroenterology 2012;142:730–3e9.

4. Hezel AF, Noel MS, Allen JN, Abrams TA, Yurgelun M, Faris JE, et al. Phase II study of gemcitabine, oxaliplatin in combination with pani-tumumab in KRAS wild-type unresectable or metastatic biliary tract and gallbladder cancer. Br J Cancer 2014;111:430–6.

5. Arrington AK, Heinrich EL, Lee W, Duldulao M, Patel S, Sanchez J, et al. Prognostic and predictive roles of KRAS mutation in colorectal cancer. Int J Mol Sci 2012;13:12153–68.

6. Pennycuick A, Simpson T, Crawley D, Lal R, Santis G, Cane P, et al. Routine EGFR and KRAS Mutation analysis using COLD-PCR in non-small cell lung cancer. Int J Clin Pract 2012;66:748–52.

7. Dobrzycka B, Terlikowski SJ, Kowalczuk O, Niklinska W, Chyczewski L, Kulikowski M. Mutations in the KRAS gene in ovarian tumors. Folia Histochem Cytobiol 2009;47:221–4.

8. O’Hara AJ, Bell DW. The genomics and genetics of endometrial can-cer. Adv Genomics Genet 2012;2012:33–47.

9. Khattak M, Fisher R, Turajlic S, Larkin J. Targeted therapy and immu-notherapy in advanced melanoma: an evolving paradigm. Ther Adv Med Oncol 2013;5:105–18.

10. Cancer Genome Atlas N. Genomic classification of cutaneous mela-noma. Cell 2015;161:1681–96.

11. Davies H, Bignell GR, Cox C, Stephens P, Edkins S, Clegg S, et al. Muta-tions of the BRAF gene in human cancer. Nature 2002;417:949–54.

12. Yao Z, Torres NM, Tao A, Gao Y, Luo L, Li Q, et al. BRAF Mutants Evade ERK-dependent feedback by different mechanisms that determine their sensitivity to pharmacologic inhibition. Cancer Cell 2015;28:370–83.

13. Nikolaev SI, Rimoldi D, Iseli C, Valsesia A, Robyr D, Gehrig C, et al. Exome sequencing identifies recurrent somatic MAP2K1 and MAP2K2 mutations in melanoma. Nat Genet 2012;44:133–9.

14. Ojesina AI, Lichtenstein L, Freeman SS, Pedamallu CS, Imaz- Rosshandler I, Pugh TJ, et al. Landscape of genomic alterations in cervical carcinomas. Nature 2014;506:371–5.

15. Cancer Genome Atlas N. Comprehensive genomic characterization of head and neck squamous cell carcinomas. Nature 2015;517:576–82.

16. Robert C, Karaszewska B, Schachter J, Rutkowski P, Mackiewicz A, Stroiakovski D, et al. Improved overall survival in melanoma with combined dabrafenib and trametinib. N Engl J Med 2015;372:30–9.

17. Planchard D, Besse B, Groen HJ, Souquet PJ, Quoix E, Baik CS, et al. Dabrafenib plus trametinib in patients with previously treated BRAF(V600E)-mutant metastatic non-small cell lung cancer: an open-label, multicentre phase 2 trial. Lancet Oncol 2016;17:984–93.

18. Larkin J, Ascierto PA, Dreno B, Atkinson V, Liszkay G, Maio M, et al. Combined vemurafenib and cobimetinib in BRAF-mutated melanoma. N Engl J Med 2014;371:1867–76.

19. Dummer R, Ascierto PA, Gogas H, Arance A, Mandala M, Liszkay G, et al. Results of COLUMBUS Part 2: A phase 3 trial of encorafenib (ENCO) plus binimetinib (BINI) versus ENCO in BRAF-mutant mela-noma. Ann Oncol 2017;28:429.

20. Chapman PB, Hauschild A, Robert C, Haanen JB, Ascierto P, Larkin J, et al. Improved survival with vemurafenib in melanoma with BRAF V600E mutation. N Engl J Med 2011;364:2507–16.

21. Corcoran RB, Atreya CE, Falchook GS, Kwak EL, Ryan DP, Bendell JC, et al. Combined BRAF and MEK inhibition with dabrafenib and trametinib in BRAF V600-mutant colorectal cancer. J Clin Oncol 2015;33:4023–31.

22. Subbiah V, Kreitman RJ, Wainberg ZA, Cho JY, Schellens JHM, Soria J-C, et al. Efficacy of dabrafenib (D) and trametinib (T) in patients (pts) with BRAF V600E–mutated anaplastic thyroid cancer (ATC). J Clin Oncol 35:15s, 2017(suppl; abstr 6023).

23. Menzies AM, Ashworth MT, Swann S, Kefford RF, Flaherty K, Weber J, et al. Characteristics of pyrexia in BRAFV600E/K metastatic mela-noma patients treated with combined dabrafenib and trametinib in a phase I/II clinical trial. Ann Oncol 2015;26:415–21.

24. Long GV, Stroyakovskiy D, Gogas H, Levchenko E, de Braud F, Larkin J, et al. Dabrafenib and trametinib versus dabrafenib and placebo for Val600 BRAF-mutant melanoma: a multicentre, double-blind, phase 3 randomised controlled trial. Lancet 2015;386:444–51.

25. Poulikakos PI, Persaud Y, Janakiraman M, Kong X, Ng C, Moriceau G, et al. RAF inhibitor resistance is mediated by dimerization of aber-rantly spliced BRAF(V600E). Nature 2011;480:387–90.

26. Corcoran RB, Dias-Santagata D, Bergethon K, Iafrate AJ, Settleman J, Engelman JA. BRAF gene amplification can promote acquired resist-ance to MEK inhibitors in cancer cells harboring the BRAF V600E mutation. Sci Signal 2010;3:ra84.

27. Nazarian R, Shi H, Wang Q, Kong X, Koya RC, Lee H, et al. Melano-mas acquire resistance to B-RAF(V600E) inhibition by RTK or N-RAS upregulation. Nature 2010;468:973–7.

28. Shi H, Hugo W, Kong X, Hong A, Koya RC, Moriceau G, et al. Acquired resistance and clonal evolution in melanoma during BRAF inhibitor therapy. Cancer Discov 2014;4:80–93.

29. Johannessen CM, Boehm JS, Kim SY, Thomas SR, Wardwell L, Johnson LA, et al. COT drives resistance to RAF inhibition through MAP kinase pathway reactivation. Nature 2010;468:968–72.

30. Wagle N, Emery C, Berger MF, Davis MJ, Sawyer A, Pochanard P, et al. Dissecting therapeutic resistance to RAF inhibition in melanoma by tumor genomic profiling. J Clin Oncol 2011;29:3085–96.

31. Wagle N, Van Allen EM, Treacy DJ, Frederick DT, Cooper ZA, Taylor-Weiner A, et al. MAP kinase pathway alterations in BRAF-mutant melanoma patients with acquired resistance to combined RAF/MEK inhibition. Cancer Discov 2014;4:61–8.

32. Paraiso KH, Fedorenko IV, Cantini LP, Munko AC, Hall M, Sondak VK, et al. Recovery of phospho-ERK activity allows melanoma cells to escape from BRAF inhibitor therapy. Br J Cancer 2010;102: 1724–30.

33. Long GV, Fung C, Menzies AM, Pupo GM, Carlino MS, Hyman J, et al. Increased MAPK reactivation in early resistance to dabrafenib/trametinib combination therapy of BRAF-mutant metastatic mela-noma. Nat Commun 2014;5:5694.

34. Hatzivassiliou G, Liu B, O’Brien C, Spoerke JM, Hoeflich KP, Haverty PM, et al. ERK inhibition overcomes acquired resistance to MEK inhibitors. Mol Cancer Ther 2012;11:1143–54.

35. Morris EJ, Jha S, Restaino CR, Dayananth P, Zhu H, Cooper A, et al. Discovery of a novel ERK inhibitor with activity in models of acquired resistance to BRAF and MEK inhibitors. Cancer Discov 2013;3:742–50.

36. Carlino MS, Todd JR, Gowrishankar K, Mijatov B, Pupo GM, Fung C, et al. Differential activity of MEK and ERK inhibitors in BRAF inhibi-tor resistant melanoma. Mol Oncol 2014;8:544–54.

37. Krepler C, Xiao M, Spoesser K, Brafford PA, Shannan B, Beqiri M, et al. Personalized pre-clinical trials in BRAF inhibitor resistant patient derived xenograft models identify second line combination therapies. Clin Cancer Res 2016;22:1592–602.

38. Ahronian LG, Sennott EM, Van Allen EM, Wagle N, Kwak EL, Faris JE, et al. Clinical acquired resistance to RAF inhibitor combinations in BRAF-mutant colorectal cancer through MAPK pathway altera-tions. Cancer Discov 2015;5:358–67.

39. Germann UA, Furey BF, Markland W, Hoover RR, Aronov AM, Roix JJ, et al. Targeting the MAPK signaling pathway in cancer: promising pre-clinical activity with the novel selective ERK1/2 inhibitor BVD-523 (ulix-ertinib). Mol Cancer Ther 2017. DOI: 10.1158/1535-7163.MCT-17-0456.

40. Yao Z, Yaeger R, Rodrik-Outmezguine VS, Tao A, Torres NM, Chang MT, et al. Tumours with class 3 BRAF mutants are sensitive to the inhibition of activated RAS. Nature 2017;548:234–8.

41. Flaherty KT, Robert C, Hersey P, Nathan P, Garbe C, Milhem M, et al. Improved survival with MEK inhibition in BRAF-mutated mela-noma. N Engl J Med 2012;367:107–14.

42. Xue Y, Martelotto L, Baslan T, Vides A, Solomon M, Mai TT, et al. An approach to suppress the evolution of resistance in BRAFV600E-mutant cancer. Nat Med 2017;23:929–37.

43. Schreuer M, Jansen Y, Planken S, Chevolet I, Seremet T, Kruse V, et al. Combination of dabrafenib plus trametinib for BRAF and MEK inhibitor pretreated patients with advanced BRAFV600-mutant melanoma: an open-label, single arm, dual-centre, phase 2 clinical trial. Lancet Oncol 2017;18:464–72.

Cancer Research. on December 17, 2020. © 2018 American Association forcancerdiscovery.aacrjournals.org Downloaded from

Published OnlineFirst December 15, 2017; DOI: 10.1158/2159-8290.CD-17-1119

Page 13: Two diseases, same person: moving towards a combined HIV and … · 70% and HIV prevalence among persons with presumptive TB (i.e. patients with TB symptoms but who may have a different

2018;8:184-195. Published OnlineFirst December 15, 2017.Cancer Discov   Ryan J. Sullivan, Jeffrey R. Infante, Filip Janku, et al.   I Dose-Escalation and Expansion Study

Phasewith MAPK Mutant Advanced Solid Tumors: Results of a First-in-Class ERK1/2 Inhibitor Ulixertinib (BVD-523) in Patients

  Updated version

  10.1158/2159-8290.CD-17-1119doi:

Access the most recent version of this article at:

  Material

Supplementary

  http://cancerdiscovery.aacrjournals.org/content/suppl/2017/12/19/2159-8290.CD-17-1119.DC1

Access the most recent supplemental material at:

   

   

  Cited articles

  http://cancerdiscovery.aacrjournals.org/content/8/2/184.full#ref-list-1

This article cites 41 articles, 9 of which you can access for free at:

  Citing articles

  http://cancerdiscovery.aacrjournals.org/content/8/2/184.full#related-urls

This article has been cited by 31 HighWire-hosted articles. Access the articles at:

   

  E-mail alerts related to this article or journal.Sign up to receive free email-alerts

  SubscriptionsReprints and

  [email protected] at

To order reprints of this article or to subscribe to the journal, contact the AACR Publications

  Permissions

  Rightslink site. Click on "Request Permissions" which will take you to the Copyright Clearance Center's (CCC)

.http://cancerdiscovery.aacrjournals.org/content/8/2/184To request permission to re-use all or part of this article, use this link

Cancer Research. on December 17, 2020. © 2018 American Association forcancerdiscovery.aacrjournals.org Downloaded from

Published OnlineFirst December 15, 2017; DOI: 10.1158/2159-8290.CD-17-1119