Titan Pharmaceuticals Inc (TTNP)

[Doctor Detroit]

Thanks for posting. This appears to be new (I'm sure it was requested by the FDA after the CRL)...no statistically significant variable (age, gender, demographics) predicted response in either probuphine or SL buprenorphine. Good, because such a varied response based on age, gender or demographics in probuphine but not SL buprenorphine could have been an excuse for more study before approval.

PREDICTORS OF RESPONSE OF A COMPARATIVE TRIAL OF SIX-MONTH BUPRENORPHINE IMPLANTS AND SUBLINGUAL BUPRENORPHINE IN STABLE OPIOID DEPENDENT PATIENTS
Lead Author: Richard N. Rosenthal, M.D., M.A.Co-Author(s): Michelle R. Lofwall, M.D., Sonnie Kim,
Pharm.D., Michael Chen, Ph.D., Katherine L. Beebe,Ph.D., Frank J. Vocci, Ph.D.
SUMMARY:
Background: A recent multicenter, double-blind, double-dummy, non-inferiority trial compared six month buprenorphine implants (BI) to daily sublingual buprenorphine (SLBPN) among 177 stable outpatients maintained on 8mg or less of SLBPN. The primary efficacy endpoint was the proportion of responders (at least four of six months without evidence of illicit opioid use by urine test and self report).
The responder rate was 96.4% for BI and 87.6% for SLBPN (difference=0.088). The 95% CI for the rate difference (0.009, 0.167) demonstrated non-inferiority. Statistical superiority in favor of BI (p=0.034) was also shown. This poster reports on a number of post hoc analyses assessing potential predictors of clinical response in both treatment arms.

Methods: Post hoc analyses were conducted with the intent-to-treat sample to determine if any baseline demographic or clinical factors such as age, gender, primary opioid of abuse, sublingual buprenorphine dose and use of supplemental buprenorphine predicted response to treatment.

Results: No variable was statistically significant as a predictor of response in either treatment group. There were trends toward increased response effect (0.242, p=0.08, 95% CI [0.048, 1.21]) in the BI group among participants older than 36 years and a female versus male effect (7.42, p=0.0625, 95% CI [0.09, 62.06]) There were no trends in the SLBPN group.

Conclusion: Although the study was not powered to detect predictors of response, the results are consistent with previous reports among opioid dependent samples receiving buprenorphine formulations, suggesting that older age is a positive predictor of treatment response. This research was supported by Braeburn Pharmaceuticals.