Abstracts online

The response to second-line therapies in patients whose tumors are refractory to BCG is generally poor. Radical cystectomy is the standard of care following BCG failure, however, some patients refuse surgery for a variety of reasons or are not medically fit surgical candidates.
The objective of this open-label, single-treatment arm, multi-center study was to evaluate the efficacy and safety of intravesical Mycobacterial cell wall DNA complex (MCC), in patients with non-muscle invasive bladder cancer (NMIBC) who were refractory to adequate intravesical BCG therapy and at high risk of progression.

Patients with high grade urothelial carcinoma (papillary NMIBC and/or carcinoma in situ [CIS]) who failed to respond to one or more courses of BCG were enrolled.
The treatment regimen consisted of 6 weekly intravesical instillations of 8 mg MCC (Induction), followed by 3 once weekly instillations at 3, 6, and 12, 18 and 24 months (Maintenance). Clinical efficacy assessments included cystoscopy, urine cytology and biopsy. Safety variables included patient reporting of adverse events (AEs) and serious adverse events (SAEs), vital signs and clinical laboratory assessments.
The primary efficacy endpoint was the disease‐free survival (DFS) rate at one year based on the intent-to-treat population (ITT) and was estimated using the Kaplan-Meier technique. Patients were considered disease-free when freedom from recurrent bladder cancer was confirmed by biopsy.

These are preliminary results based on an interim analysis. Between November 2006 and April 2009, a total of 129 patients were enrolled from 25 centers in US and Canada. The median age was 71 years (range of 41‐90). All 129 patients were white and 95 (73.6%) of them were male. At study entry, 91 (70.5%) patients had CIS (either primary or concomitant with papillary) and 38 (29.5%) had papillary tumors.
The overall one‐year DFS rate was 25.0% with a median DFS interval of 177 days for the ITT population. When subdivided by tumor type at study entry, patients with CIS tumors (primary or concomitant with papillary) had a one‐year DFS rate of 21.0%, while patients with only papillary tumors had a one-year DFS rate of 35.1%. Intravesical administration of MCC was well tolerated - most AEs were mild to moderate in severity and few lead to discontinuation of treatment. Two SAEs (hematuria, urinary tract infection) were reported as being possibly related to the investigational treatment.

The preliminary results from the interim analysis of our prospective trial indicates that MCC may provide an alternative to cystectomy for patients with BCG-refractory NMIBC.