Cookies on this website
We use cookies to ensure that we give you the best experience on our website. If you click 'Continue' we'll assume that you are happy to receive all cookies and you won't see this message again. Click 'Find out more' for information on how to change your cookie settings.

<jats:p> 406 </jats:p><jats:p> Background: Intravesical BCG has been the mainstay of therapy following TURBT for intermediate risk NMIBC for many years and is thought to act through activation of non-specific local immunity. With the recent success of checkpoint inhibitor treatment in metastatic bladder cancer, we sought to investigate the anti-PD1 inhibitor pembrolizumab as a potential agent for use in patients with intermediate risk NMIBC in a phase I/II study. The primary aim of the phase I safety run-in was to assess the safety and tolerability of intravesical pembrolizumab after TURBT in patients with intermediate risk NMIBC. Methods: Eligible patients had recurrent NMIBC for which adjuvant treatment post TURBT was a reasonable treatment option, ECOG PS 0-1 and adequate end organ function. Pembrolizumab was administered by intravesical instillation once weekly for a total of 6 doses. Intra-patient dose escalation was performed in three paired patient cohorts with doses starting at 50mg and increasing through 100mg to a maximum of 200mg. Adverse events (AEs) were assessed using CTCAE v4.03 with dose limiting toxicity (DLT) defined as a clinically significant, drug related, grade 4 haematological or ≥ grade 3 non-haematological toxicity occurring within 7 days of administration of the first treatment at a given dose for that patient. Results: In the first 4 patients treated, no DLTs were seen during dose escalation. Drug-related AEs included Grade 1 dysuria, fatigue and nausea. Grade 1-2 urinary tract infections, Grade 1 cystitis and Grade 3 urosepsis (SAE) were observed but assessed as probably not related to pembrolizumab. Recruitment of a final cohort of two patients at repeated doses of 200mg is ongoing to confirm safety and tolerability of this dose. Conclusions: Administration of intravesical pembrolizumab was safe and well tolerated in patients with NMIBC following TURBT. A randomised, parallel group, phase II marker-lesion study to assess the safety, efficacy and tolerability of either intravesical pembrolizumab or intravenous pembrolizumab in a larger cohort of patients with intermediate risk recurrent NMIBC is planned. Clinical trial information: NCT03167151. </jats:p>

Original publication

DOI

10.1200/jco.2019.37.7_suppl.406

Type

Conference paper

Publisher

American Society of Clinical Oncology (ASCO)

Publication Date

01/03/2019

Volume

37

Pages

406 - 406