The Food and Drug Administration approved pembrolizumab (KEYTRUDA, Merck & Co. Inc.) for the treatment of patients with Bacillus Calmette-Guerin (BCG)-unresponsive, high-risk, non-muscle invasive bladder cancer (NMIBC) with carcinoma in situ (CIS) with or without papillary tumours who are ineligible for or have elected not to undergo cystectomy. 

Efficacy was investigated in KEYNOTE-057 (NCT, a multicentre, single-arm trial that enrolled 148 patients with high-risk NMIBC, 96 of whom had BCG-unresponsive CIS with or without papillary tumours.

Patients received pembrolizumab 200 mg every 3 weeks until unacceptable toxicity, persistent or recurrent high-risk NMIBC or progressive disease, or up to 24 months of therapy without disease progression.

The major efficacy outcome measures were complete response (as defined by negative results for cystoscopy [with TURBT/biopsies as applicable], urine cytology, and computed tomography urography [CTU] imaging) and duration of response.

The complete response rate in the 96 patients with high-risk BCG-unresponsive NMIBC with CIS was 41% (95% CI: 31, 51) and median response duration was 16.2 months (0.0 , 30.4 ).

Forty-six percent (46%) of responding patients experienced a complete response lasting at least 12 months.

The most common adverse reactions (incidence ≥10%) in patients who received pembrolizumab in KEYNOTE-057 were fatigue, diarrhoea, rash, pruritis, musculoskeletal pain, haematuria, cough, arthralgia, nausea, constipation, urinary tract infection, peripheral edema, hypothyroidism, and nasopharyngitis 

The recommended pembrolizumab dose is 200 mg every 3 week.

Source: The Food and Drug Administration (FDA)