Combination Therapy for Gastric Cancer
(MAHOGANY Trial)

Recruiting in Palo Alto (17 mi)

+72 other locations

Age: 18+

Sex: Any

Travel: May Be Covered

Time Reimbursement: Varies

Trial Phase: Phase 2 & 3

Waitlist Available

Sponsor: MacroGenics

No Placebo Group

Prior Safety Data

Trial Summary

What is the purpose of this trial?This is a Phase 2/3, randomized, open-label study for the treatment of patients with HER2-positive Gastric cancer (GC) or Gastroesophageal Junction (GEJ) cancer conducted in two parts. Part A is a single-arm cohort (Cohort A, 40 to 110 patients) will evaluate safety and efficacy of margetuximab plus retifanlimab. Part B Part 1 has 4 arms (50 patients/arm). Patients will be randomized to margetuximab plus retifanlimab plus chemotherapy, margetuximab plus tebotelimab, plus chemotherapy, margetuximab plus chemotherapy, or trastuzumab plus chemotherapy.

Eligibility Criteria

This trial is for adults with untreated advanced HER2+ gastric or gastroesophageal junction cancer. They should have a good performance status, measurable tumor lesions, and no central nervous system metastases. Prior systemic treatment is okay if there's been a disease-free period of at least 6 months.

Inclusion Criteria

My cancer is advanced, cannot be surgically removed, and is HER2 positive.

Life expectancy ≥ 6 months

I had treatment before or after surgery and have been disease-free for at least 6 months.

+7 more

Exclusion Criteria

My cancer is MSI-H.

My cancer has spread to my brain.

I have received immunotherapy before surgery or alongside other treatments.

+3 more

Participant Groups

The study tests combinations of margetuximab with retifanlimab or tebotelimab plus chemotherapy against trastuzumab with chemo in two parts: initial safety/efficacy assessment (Part A) and randomized comparison to find the best combo (Parts B1 & B2).

5Treatment groups

Experimental Treatment

Active Control

Group I: Margetuximab, tebotelimab and chemotherapy armExperimental Treatment3 Interventions

margetuximab plus tebotelimab plus investigator choice of chemotherapy options. Chemotherapy options: capecitabine and oxaliplatin (XELOX) or modified 5-FU, leucovorin, and oxaliplatin regimen 6 (mFOLFOX-6)

Group II: Margetuximab, retifanlimab, and chemotherapy armExperimental Treatment3 Interventions

margetuximab plus retifanlimab plus investigator choice of chemotherapy options. Chemotherapy options: capecitabine and oxaliplatin (XELOX) or modified 5-FU, leucovorin, and oxaliplatin regimen 6 (mFOLFOX-6)

Group III: Margetuximab and chemotherapy armExperimental Treatment2 Interventions

margetuximab plus investigator choice of chemotherapy options. Chemotherapy options: capecitabine and oxaliplatin (XELOX) or modified 5-FU, leucovorin, and oxaliplatin regimen 6 (mFOLFOX-6)

Group IV: Chemotherapy-free armExperimental Treatment2 Interventions

margetuximab plus retifanlimab

Group V: Trastuzumab and chemotherapy armActive Control2 Interventions

Trastuzumab plus investigator choice of chemotherapy options. Chemotherapy options: capecitabine and oxaliplatin (XELOX) or modified 5-FU, leucovorin, and oxaliplatin regimen 6 (mFOLFOX-6)

Chemotherapy is already approved in European Union, United States, Canada, Japan, China, Switzerland for the following indications:

🇪🇺 Approved in European Union as Chemotherapy for: