Kadmon will head to US regulators next year with a strong case to make for accelerated approval of KD025 in graft-vs-host disease. Response rates easily cleared a 30% ORR threshold at an interim analysis of the phase II Rockstar trial, and Kadmon shares jumped 12% to a 14-month high. KD025 is thought to work by inhibiting Rock2, which modulates an inflammatory response pathway; these findings suggest efficacy at least in line with Imbruvica, which was approved on data generated in a less refractory population. Unless results substantially deteriorate at the final analysis, or an unexpected safety issue rears its head, a green light for patients who have received at least two prior lines of therapy looks likely; Imbruvica is approved in all steroid-refractory patients. Analysts have pencilled in KD025 sales of $473m in GVHD by 2024, EvaluatePharma’s sellside consensus shows, though this bullish outlook presumably depends on the absence of more effective rivals. Incyte is one to watch here, with trials of both Jakafi and its follow-on asset itacitinib ongoing, while Amgen has AMG 592, an IL-2 and IgG fusion protein, in a mid-stage chronic GVHD trial.
|Cross-trial comparison of chronic GVHD results|
|Imbruvica (Study 1129)||KD025 (Rockstar)|
|Steroid-refractory, ORR at median 13.9mth follow-up||ORR 2mth after completing enrollment|
|420mg once daily (n=42)||200mg once daily (n=63)||200mg twice daily (n=63)|
|Median prior therapies||2||3||4|
|Source: Company presentations, US drug label.|