A Trial of PF-07901800 (TTI-621) for Patients With Hematologic Malignancies and Selected Solid Tumors

MAJOR ELIGIBILITY CRITERIA:

Phase 1a Escalation

• Histologically documented, measurable, advanced lymphomas, transfusion-independence

Phase 1b Expansion (Part 2 and 3) • Advanced malignancy: IBCL, ABCL, cHL, AML, ALL, MDS,
MPN, SCLC, PTCL and CTCL; measurable disease who have relapsed or are refractory following
at least 2 prior systemic therapeutic attempts (1 prior systemic attempt for PTCL). For
CTCL, extracorporeal photochemotherapy (ECP) considered a systemic therapy. Local radiation
and topical agents are not systemic therapies.

Phase 1b dose optimization (Part 4)

• Histologically confirmed diagnosis of CTCL (both Mycosis Fungoides and Sezary Syndrome):
Failed at least 2 prior systemic therapies for CTCL (Systemic therapy does not include
local radiation therapy or topical agents); History of histologically documented diagnosis
of CTCL stage IB to IVB

Inclusion Criteria (all subjects):

   - Advanced measurable malignancy with previously progressed on, or currently progressing
   on standard anticancer therapy or for whom no other approved conventional therapy
   exists

   - Eastern Cooperative Oncology Group (ECOG) 0-2

   - Adequate hematologic, hepatic, renal, and coagulation function; fresh or archived
   tumor tissue available for immunohistochemistry

   - Recovery from prior treatments and/or surgeries; no history of hemolytic anemia or
   bleeding diathesis.

   - AML M3 (French American British, FAB, classification) (i.e., acute promyelocytic
   leukemia [APL]) excluded

Exclusion Criteria:

   - Known current central nervous system disease involvement or untreated brain metastases

   - Allogeneic transplant within 30 days prior to the planned start of treatment or
   subjects with active graft-vs-host disease with the exception of Grade 1 skin
   involvement

   - History of hemolytic anemia or bleeding diathesis