Activity and tolerability of maintenance avelumab immunotherapy after first line polychemotherapy including platinum in patients with locally advanced or metastatic squamous cell penile carcinoma: PULSE.

Background Metastatic Squamous cell Penile Carcinoma (mSCPC) is an orphan disease with a virally induced oncogenesis. PD-L1 expression rate is around 60% with a strong correlation between PD-L1 in the primary tumour and metastases. The first line systemic treatment relies on platinum-based chemotherapies with a median progression free survival and overall survival around 7.5 and 16 months, respectively. Immunotherapies targeting PD-1/PD-L1 axis are effective in other squamous cell or HPV related cancers. Methods PULSE is a prospective multicenter open label single arm phase II study. Thirty-two patients will be enrolled after a radiological assessment showing a non-progressive disease after 3 to 6 cycles of a first line platinum-based polychemotherapy. Patients will receive Avelumab injections 10mg/ kg every two weeks until progression or unacceptable toxicity. The primary endpoint will be the progression free survival (PFS) according to RECIST v1.1 criteria. Secondary endpoints will include PFS according to iRECIST criteria, overall survival, quality of life, safety. Ancillary explorations will include assessing blood and tissue biomarkers for association with clinical benefit. Discussion After the first line, the prognosis remains poor with no consensus on a second line systemic treatment in locally advanced or mSCPC. PULSE trial is the first study that assess an anti PD-L1 immunotherapy in maintenance among patients with locally advanced or mSCPC. NCT NUMBER : NCT03774901.