A Study of PF-07260437 in Advanced or Metastatic Solid Tumors (C4431001)

Pfizer

Status and phase: Terminated; Phase 1

Conditions: Ovarian Neoplasms; Breast Neoplasms; Endometrial Neoplasms

Treatments: Drug: PF-07260437; Diagnostic Test: B7-H4 IHC

Study type: Interventional

Funder types: Industry

Identifiers

NCT05067972

C4431001

Details and patient eligibility

About

A study to evaluate the safety, tolerability, pharmacokinetics (PK), pharmacodynamics (PD), and antitumor activity of PF-07260437, a B7-H4 x CD3 bispecific mAb, in participants aged ≥18 years of age with advanced or metastatic breast cancer, ovarian cancer or endometrial cancer. Adult participants with other advanced or metastatic high B7-H4 expressing tumors may be considered after discussion with and approval from sponsor.

Enrollment: 30 patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Part 1: Histological/cytological diagnosis of selected locally advanced or metastatic breast cancer, endometrial cancer and ovarian cancer
• Part 2A:In second line or more, participants with histological/cytological diagnosis of locally advanced or metastatic HR+ HER2- breast cancer showing high B7-H4 expression
• Part 2B: In second line or more participants with histological or cytological diagnosis of locally advance or metastatic HR+ Her2- breast cancer or triple negative breast cancer (TNBC) with no biomarker pre-selection
• Part 2C: In second line or more participants with histological diagnosis of locally advance or metastatic triple negative breast cancer with high B7-H4 expression
• Thyroid function within normal laboratory range; in participants with abnormal thyroid function if Free T4 is normal and participant is clinically euthyroid, participants is eligible

Exclusion criteria

• Participants with any active malignancy within 3 years prior to enrollment
• Participants with advanced/metastatic, symptomatic, visceral spread, that are at risk of life-threatening complications in the short term (including participants with massive uncontrolled effusions [pleural, pericardial, peritoneal], pulmonary lymphangitis, and over 50% liver involvement).
• History of Grade ≥3 immune mediated adverse events (including liver function tests that where considered drug related and cytokine release syndrome) that was considered related to prior immune modulatory therapy (eg, immune checkpoint inhibitors, co stimulatory agents, etc.) and required immunosuppressive therapy within 1 year of treatment.

Trial design

Primary purpose: Treatment

Allocation: Non-Randomized

Interventional model: Sequential Assignment

Masking: None (Open label)

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30 participants in 4 patient groups

Monotherapy dose escalation (Part 1)

Experimental group

Description:

Participants will receive PF-07260437

Treatment:

Drug: PF-07260437

Dose Expansion (Part 2A) - Tumor specific Arm A

Experimental group

Description:

Participants will receive PF-07260437

Treatment:

Diagnostic Test: B7-H4 IHC

Drug: PF-07260437

Dose Expansion (Part 2B) - Tumor specific Arm B

Experimental group

Description:

Participants will receive PF-07260437

Treatment:

Diagnostic Test: B7-H4 IHC

Drug: PF-07260437

Dose Expansion (Part 2C) - Tumor specific Arm C

Experimental group

Description:

Participants will receive PF07260437

Treatment:

Diagnostic Test: B7-H4 IHC

Drug: PF-07260437