Part I was intended to evaluate the effect of the addition of TG-1101 to ibrutinib on overall response rate (ORR) in approximately the first 200 patients enrolled, to support a filing for accelerated approval of TG-1101
Part II was meant to evaluate the effect of the addition of TG-1101 to ibrutinib on progression-free survival (PFS) in all study patients (approximately 330), to support a filing for full approval of TG-1101.
The amended protocol contains the following substantive changes:
At the new study size, the study is 90% powered to show a statistically significant improvement in ORR, with the minimal detectable difference of approximately 20% (absolute difference between the arms). Additionally, patients will be followed until progression, but the study will no longer be powered for PFS.
The company expects that it will complete enrollment in the revised trial by year end 2016, and will have topline data available in the first half of 2017. If the results of the study are positive, the company plans to request a pre-BLA meeting to discuss the data and a filing strategy with the FDA. The company has communicated with the FDA regarding its intention to file a BLA for accelerated approval if the results are positive and the FDA has agreed that a pre-BLA meeting can be requested based on ORR data from the GENUINE study. Assuming a positive outcome of a pre-BLA meeting, targeted to occur in the fourth quarter of 2017, the company believes it could file a BLA in the first half of 2018.
Michael S. Weiss, the company's executive chairman and interim chief executive officer, stated, "Today's announcement marks an important milestone for the Company. Given the GENUINE enrollment challenges we've faced to date, we are very excited to accelerate the trial to a rapid conclusion, while also maintaining the ability to potentially file the data for accelerated approval. The GENUINE study, as amended, remains a robust, randomized clinical trial, which we believe, if positive, could support accelerated approval for patients with relapsed/refractory high-risk CLL. Moreover, we believe the amended study and revised regulatory strategy is consistent with the recent accelerated approvals for novel agents in CLL, which notably were not pursuant to an SPA but occurred after the finding of positive ORR results.
“Importantly, with completion of enrollment now expected by year end, we and our clinical trial sites can focus our resources on completing our UNITY-CLL phase III trial as quickly as possible. Early enrollment in UNITY-CLL is very encouraging and we anticipate that study will be fully enrolled before filing a BLA for the GENUINE study. UNITY-CLL remains unchanged and unaffected by the amendments to the GENUINE study, and if positive, could support full approval for both TG-1101 and TGR-1202 based on its primary endpoint of PFS."
Mr. Weiss continued, "We have greatly appreciated all of the guidance and counsel from the FDA in designing our clinical programs and we look forward to continuing our collaborative working relationship as we accelerate toward the conclusion of enrollment into the GENUINE study this year and ORR data in the first half of 2017."