Oncofid-P-B: a novel treatment for BCG unresponsive carcinoma in situ (CIS) of the bladder: Results of a prospective European Multicentre study at 15 months from treatment start.

Abstract Purpose This study reports the safety and efficacy of Oncofid−P-B, a novel compound under development by Fidia Farmaceutici S.p.A. with specific binding to CD44 receptor, in patients with CIS unresponsive or intolerant to BCG. Materials and Methods This is a phase 1 open-label, single arm, multicenter European study to assess safety, tolerability and efficacy of Oncofid-P-B administered in 20 patients with CIS ± Ta-T1, unresponsive or intolerant to BCG, unwilling or unfit for cystectomy. Oncofid-P-B was administered by intravesical instillation for 12 consecutive weeks (intensive phase) followed, in CR patients, by 12 monthly instillations (maintenance phase). The primary objective was the overall safety profile. Secondary objectives included: i) any evidence of antitumor activity, ii) patient's compliance, iii) systemic absorption. The CR was defined as a negative cystoscopy, negative biopsy of the urothelium and negative cytology. Results At the end of the intensive phase, 15 of the 20 enrolled patients (75%), achieved the CR. Patients still in CR after 3, 6, 9 and 12 months of maintenance phase were 13 (65%), 12 (60%), 9 (45%) and 8 (40%), respectively. Only seven (5 mild and 2 moderate) drug-related AEs were reported in three patients. No drug related serious AEs and no drug related withdrawals have been reported. In all plasma samples, the drug concentratiosn was below the LLOQ (1ng/ml). Conclusions Oncofid-P-B is very safe, well tolerated and highly effective (75% CR) when administered weekly for up to 12 consecutive weeks (75% CR), with 40% CR still after 15 months from treatment start.