FDA Approval Summary: Retifanlimab for the treatment of adult patients with metastatic or inoperable locally recurrent squamous cell carcinoma of the anal canal
In brief
Retifanlimab plus chemotherapy extends progression-free survival by about two months in advanced anal cancer
In the phase III POD1UM-303 trial, adding retifanlimab to carboplatin-paclitaxel increased median progression-free survival to 9.3 months versus 7.4 months with chemotherapy alone. Overall survival was not yet statistically different, and a single-agent retifanlimab showed a 14% response rate in second-line patients. The drug now offers a new option for unresectable or metastatic disease, though its impact on long-term survival remains uncertain.
- Journal
- Clinical cancer research : an official journal of the American Association for Cancer Research (Q1)
- Published
- 5 August 2026
- Study design
- Non-randomized / quasi-experimental trial
- Evidence level
- Level 2, Moderate (CEBM 2b)
- Authors
- Shruti U Gandhy, Sandra J Casak, May Tun Saung, Pallavi S Mishra-Kalyani, Shenghui Tang, Doris Auth, et al.
- PMID
- 42555229
- DOI
- 10.1158/1078-0432.CCR-26-0618
Why clinicians should know about it
- Picked for Oncology and Radiation Oncology (paper of the day, 6 August 2026): FDA approval summary of retifanlimab for metastatic anal SCC
Abstract
On May 15, 2025, the Food and Drug Administration approved retifanlimab in combination with carboplatin and paclitaxel for treating unresectable or metastatic squamous cell carcinoma of the anal canal (SCAC), and as a single agent for second-line SCAC treatment. These approvals were based on POD1UM-303 and POD1UM-202 trials. In POD1UM-303, 308 patients with no prior systemic treatment for advanced disease were randomized 1:1 to receive retifanlimab or placebo, both combined with carboplatin and paclitaxel. The primary efficacy outcome was progression-free survival (PFS) assessed by blinded independent central review, with overall survival (OS) as a key secondary endpoint. The trial demonstrated a statistically significant PFS improvement with a hazard ratio (HR) of 0.63 (95% CI: 0.47, 0.84, p-value 0.0006). Median PFS was 9.3 months (95% CI: 7.5, 11.3) and 7.4 months (95% CI: 7.1, 7.7) in the retifanlimab and placebo arms, respectively. Interim OS results were not statistically significant (HR 0.70 [95% CI: 0.49, 1.01]), although the point estimate for OS was 29.2 months (95% CI: 24.2, NE) in the retifanlimab arm and 23 months (95% CI: 15.1, 27.9) for placebo. Second-line approval was based on POD1UM-202, a single-arm trial of 94 patients receiving single-agent retifanlimab. The independent centrally assessed overall response rate was 14% (95% CI: 8, 23). No new adverse safety signals were identified. The approval of retifanlimab as a single agent or in combination with chemotherapy provides a new therapeutic option for patients with unresectable or metastatic SCAC.
Abstract as published, via PubMed.
For healthcare professionals. The summary is generated by AI from the published abstract, and the evidence level is assigned automatically from the study design on the Oxford CEBM hierarchy. Neither is medical advice. Read the full paper before changing practice.