Today, the U.S. Food and Drug Administration (FDA) approved pembrolizumab (Keytruda) for the treatment of patients with bacillus Calmette-Guérin (BCG)-unresponsive, high-risk, non–muscle invasive bladder cancer with carcinoma in situ with or without papillary tumors who are ineligible for or have elected not to undergo cystectomy.
Efficacy was investigated in KEYNOTE-057, a multicenter, single-arm trial that enrolled 148 patients with high-risk non–muscle invasive bladder cancer, 96 of whom had BCG-unresponsive carcinoma in situ with or without papillary tumors. Patients received 200 mg of pembrolizumab every 3 weeks until unacceptable toxicity, persistent or recurrent high-risk non–muscle invasive bladder cancer 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 transurethral resection of bladder tumor/biopsies as applicable], urine cytology, and computed tomography urography imaging) and duration of response.
The complete response rate in the 96 patients with high-risk BCG-unresponsive non–muscle invasive bladder cancer with carcinoma in situ was 41% (95% confidence interval = 31%–51%) and median response duration was 16.2 months (0.0+ to 30.4+). Forty-six percent 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, diarrhea, rash, pruritis, musculoskeletal pain, hematuria, cough, arthralgia, nausea, constipation, urinary tract infection, peripheral edema, hypothyroidism, and nasopharyngitis.
The recommended dose of pembrolizumab is 200 mg every 3 weeks.