A Study of Retifanlimab After Chemoradiation in People With Anal Cancer

What this study involves

The registry says this study is recruiting. Individual locations may have different availability.

Study type

Interventional

Phase

Phase 2

Age range

18 years - Not specified

Sex eligible

All sexes

Healthy volunteers

Not accepted

Participants

25 Estimated

These are starting points, not an eligibility decision. The research team must review the full requirements.

About the research

Participants will receive retifanlimab during 28-day treatment Cycles and will continue to receive retifanlimab for up to 6 Cycles (up to 12 Cycles with study doctor approval) unless the participant's cancer comes back, have serious side effects and cannot continue study treatment, or the study doctor thinks it is in the participant's best interest to stop.

Who may be able to participate?

The list below is the sponsor’s full registry wording. It can include conditions, prior treatment, test results and other requirements. A match in search does not mean you qualify.

Inclusion Criteria:

• Subject or legally authorized representative is willing and able to provide written informed consent.
• Age ≥ 18 on day of signing informed consent.
• Consent for use of archival tissue and blood draws for research purposes.
• Documentation of Disease

o Patients must have pathologically confirmed anal squamous cell carcinoma.

° Pathology confirmation of the primary tumor at time of initial diagnosis is acceptable.
* Disease Specific Criteria

• Patients must have MRD after completion of definitive-CRT defined as:

• Detectable on the last day of or after completing definitive-CRT.
• In patients with MRD within 6 months of CRT completion, patients with no overt clinical or radiographic progression will be eligible, the treatment response evolves for up to 6-months after completion of CRT. The ACT II trial demonstrated that 70% of patients with an incomplete response to CRT at 3-months achieved a clinical complete response by 6-months \[18\].
• ctDNA will be assessed using Natera Signatera, a CLIA- validated tumor informed ctDNA assay, which MSK patients currently undergo baseline, on-treatment, and surveillance monitoring as standard of care.
• As patients will not have measurable radiographic disease at time of enrollment, RECIST will not be used for study.
• Patients must sign informed consent within 4 weeks of positive ctDNA result. The 4 weeks is considered from the date that the ctDNA resulted, and not the date it is drawn.
• Patients must have completed definitive CRT per institutional standards or as determined appropriate by the principal investigator.
• Resolution of all non-hematologic toxicities of prior therapy or surgical procedures to baseline or Grade 1 (except for hypothyroidism requiring medication, which must have resolved to Grade ≤2), alopecia, and other toxicities considered clinically nonsignificant and/or stable on supportive therapy as determined by the investigator.

o Lymphopenia is a known side effect of CRT, which can take months to resolve \[4\], and is not an exclusion to eligibility.
* ECOG Performance Status of ≤ 2
* Required Organ Function

• Adequate hematologic function defined as follows:

• Absolute neutrophil count (ANC) ≥= 1,000 cells/mm3
• Platelets ≥ 75,000 cells/mm3
• Hemoglobin ≥ 9 g/dl
• Adequate renal function defined as follows:

• Creatinine clearance (CrCL) of ≥30 mL/min by the Cockcroft-Gault formula (Note: For agents for which renal excretion is not a major route of clearance and for which renal toxicity is not an issue, the threshold for creatinine clearance should be ≥30 mL/min.):

CrCl (mL/min) = \[ (140 - Age) × Weight (kg)\] / \[72 × Serum Creatinine (mg/dL)\], multiplied by 0.85 for females.

• Adequate hepatic function defined as follows:

• Total bilirubin ≤ 1.5 x institutional upper limit of normal (ULN) (patients with known Gilbert's disease who have bilirubin level ≤ 3 x ULN may be enrolled)
• AST and ALT ≤2.5 x institutional ULN
• Adequate cardiac function defined as follows:

• Patients with known history or current symptoms of cardiac disease, or history of treatment with cardiotoxic agents, should have a clinical risk assessment of cardiac function using the New York Heart Association Functional Classification.
• To be eligible for this trial, patients with known congestive heart failure should be class 2B or better (see Appendix II: New York Heart Association (NYHA) Functional Classification).

Exclusion Criteria:

• Presence of metastatic or recurrent disease.
• Active infection requiring parenteral antibiotic(s).
• Known active TB (Bacillus tuberculosis) infection.
• Known psychiatric or substance abuse disorders that would interfere with cooperation with the requirements of the trial.
• Active immune disease requiring systemic immunosuppression in excess of physiologic maintenance doses of corticosteroids (\>10mg of prednisone or equivalent).
• Interstitial lung disease or active noninfectious pneumonitis.
• Known active CNS metastases and/or carcinomatous meningitis.
• History of allogeneic bone marrow/stem, cell, or solid organ transplant.
• Pregnant or nursing or expecting to conceive or father children within the projected duration of the trial.

o Participants of child-bearing potential must agree to use adequate contraception (hormonal or barrier method of birth control; abstinence) during study therapy and for 6 months following the completion of study therapy.
* Uncontrolled infection with human immunodeficiency virus (HIV). HIV-infected patients on effective anti-retroviral therapy with undetectable viral load and CD4+ count \>300/μL within 6 months are eligible.
* Known to be hepatitis B virus (HBV) surface antigen, or any other positive test for HBV indicating acute or chronic infection. Patients who are receiving or who have received anti-HBV therapy and have undetectable HBV DNA prior to study entry are eligible.
* Known active hepatitis C virus (HCV) as determined by positive serology and confirmed by polymerase chain reaction (PCR). Patients on or who have received antiretroviral therapy are eligible provided they are virus-free by PCR for at least 6 months prior to study entry.
* Receipt of a live vaccine within 28 days of planned start of study drug. Note: Examples of live vaccines include, but are not limited to, the following: measles, mumps, rubella, chicken pox/zoster, yellow fever, rabies, BCG, and typhoid vaccine. Seasonal influenza vaccines for injection are generally killed virus vaccines and are allowed; however, intranasal influenza vaccines (e.g., FluMist®) are live-attenuated vaccines and are not allowed.
* Prior therapy with an anti-PD-1, anti-PD-L1, or anti-CTLA-4 agent.
* History of allergic reaction to the study agent(s), compounds of similar chemical or biologic composition to the study agent (s) (or any of its excipients).

Treatment, groups and participation

The registry may describe treatments and study duration without a complete visit calendar. Ask the study team for the exact schedule, procedures, risks, costs and alternatives. Keep your usual care plan unless your treating clinician tells you otherwise.

Assignment

Not applicable

Masking

No masking

What researchers are measuring

Outcome measures describe what is being studied. They are not proof that a treatment works.

Primary measures

Research locations (7)

The overall study status and a local site’s status can differ. Confirm that location’s availability before traveling.

7 locations

Study team and timeline

Lead sponsor

Memorial Sloan Kettering Cancer Center

Study start

Nov 4, 2026 Actual

Primary completion

Nov 4, 2029 Estimated

Study completion

Nov 4, 2029 Estimated

First posted

Nov 10, 2026 Actual

Last updated

Nov 10, 2026 Actual

Official study contacts