Mevrometostat Treatment of Relapsed/Refractory SCLC, Castration Resistant Prostate Cancer, and Follicular Lymphoma

Summary

Objectives

This is an open label, multi center, Phase 1 dose escalation and dose expansion study of
mevrometostat (PF-06821497) administered orally BID as a single agent or in combination
with SOC to patients with CRPC, SCLC, and FL. The study consists of Part 1, Part 2 and
the Japan and China monotherapy cohorts Part 1A will evaluate safety and target
modulation of mevrometostat monotherapy in patients with SCLC, FL and CRPC. Mevrometostat
will be administered as monotherapy in escalating doses to patients with FL (Part 1B) and
mCRPC (Part 1C) to determine the monotherapy MTD. In Part 2A (dose escalation, RP2D
finding for dose escalation), mevrometostat will be administered in combination with SOC
to patients with mCRPC and SCLC. Japan and China monotherapy cohorts will evaluate the
safety, antitumor activity and PK of single agent mevrometostat in Japanese and Chinese
patients. In Part 2B (dose expansion), patients with mCRPC will be randomized (1:1 ratio)
to receive either SOC or mevrometostat in combination with SOC. Part 2B will assess the
efficacy of mevrometostat at the RP2D in combination with SOC in patients with mCRPC in
comparison to SOC alone. Part 2C will explore the efficacy of mevrometostat given at a
different dose/dosing regimen than 2B in combination with SOC in patients with mCRPC.