Recombinant adenovirus interferon alfa with Syn3 (rAd–IFNa/Syn3) may be effective in patients with high grade (HG) refractory/relapsed (R/R) non-muscle-invasive bladder cancer (NMIBC) after bacillus Calmette-Guerin (BCG) therapy, according to a study published in the Journal of Clinical Oncology.
Patients with HG NMIBC experience high rates of relapse after BCG, the current preferred therapy. While radical cystectomy is an effective secondary treatment for persistent or recurrent tumors, many patients opt not to undergo the procedure due to high rates of comorbidities and complications.
For this phase 2 study (ClinicalTrials.gov Identifier: NCT01687244), researchers randomly assigned 43 patients with HG BCG R/R NMIBC to receive intravesical rAd–IFNa/Syn3 1 x 1011 viral particles(vp)/mL or 3 x 1011 vp/mL. Patients who did not experience recurrence at months 3, 6, and 9, were retreated at months 4, 7, and 10.
Patients in the low-dose arm had a similar 12-month high-grade recurrence-free survival (RFS) rate (33.3%; 90% CI, 16.8-53.6) to the high-dose arm (36.8%; 90% CI, 18.8-58.2). Overall, the RFS was 35% (90% CI, 22.6-49.2%) 12 months after initiation.
Two patients experienced recurrence at 21 and 28 months, respectively.
rAd–IFNa/Syn3 demonstrated a favorable safety profile; although nearly all patients experienced an adverse effect (AE), no grade 4 to 5 AEs or AE-related discontinuations were reported. The most frequently reported AEs were micturition urgency, dysuria, fatigue, pollakiuria, hematuria, and nocturia.
The study authors conclude by noting that “a phase III trial of high-dose rAd–IFNa/Syn3, which provided longer median HG RFS and equivalent biosafety, is ongoing.”
- Shore ND, Boorjian SA, Canter DJ, et al. Intravesical rAd–IFNa/Syn3 for patients with high-grade, bacillus Calmette-Guerin-refractory or relapsed non-muscle-invasive bladder cancer: a phase II randomized study [published online August 23, 2017]. J Clin Oncol. doi: 10.1200/JOC.2017.72.3064