The ‘GIST’ of things: Bayer’s investigational drug on FDA Fast Track

WAYNE, N.J.—The U.S. Food and Drug Administration (FDA) hasgranted Fast Track designation to Bayer HealthCare Pharmaceuticals Inc.'sinvestigational compound regorafenib. The compound is developed for thetreatment of patients with metastatic and/or unresectable (inoperable)gastrointestinal stromal tumors (GIST) whose disease has continued to progressdespite being previously treated with at least imatinib and sunitinib. Theinvestigational compound received orphan drug status from the FDA in February.

The Fast Track designation is part of a process on the partof the FDA to "facilitate the development and expedite the review of drugs totreat serious diseases and fill an unmet medical need," according to the FDAwebsite. The designation must be requested by the drug company. Drugs thatreceive the Fast Track designation are eligible for benefits such as morefrequent meetings with the FDA, eligibility for accelerated approval, dispute resolutionand rolling review, in which a company can submit their New Drug Application asthey complete sections of the application, rather than completing each sectionand submitting them all together.

"There is an unmet medical need for this specific patientpopulation," says Dr. Kemal Malik, Head of Global Development and memberof the Bayer HealthCare Executive Committee. "This milestone is animportant step in the overall development of regorafenib."

Bayer began enrolling patients in its Phase III study ofregorafenib in January. The study was a randomized, double-blind,placebo-controlled study of regorafenib plus best supportive care versus aplacebo plus best supportive care for patients with metastatic and/orunresectable GIST whose disease had progressed despite receiving priortreatment with at least imatinib and sunitinib. The trial is estimated toenroll 170 patients, randomized in a 2-to-1 ratio to receive either theregorafenib treatment or the placebo. Of those subjects receiving the placebo,if any experience disease progression, they have a cross-over option of beingoffered open-label regorafenib treatment.

The trial's primary endpoint is progression-free survival,while the secondary endpoints are overall survival, time to progression, diseasecontrol rate, tumor response rate, duration of response and safety.Additionally, all participating patients will enter the Survival Follow-upPeriod upon discontinuation of study treatment, which is when the assessment ofsurvival status will be performed.

GIST is the most common form of sarcoma that involves the GItract, and most primary tumors occur in the stomach or small intestine. It isestimated that 11 to 20 patients per million per year have GIST, and theinternational prevalence of it is comparable to that in the United States. Anestimated 4,500 to 6,000 new cases of GISTs are diagnosed in the U.S. eachyear, and about 1,500 of those cases have already metastasized by the time theyare discovered. GISTs can be life threatening if they metastasizes or areinoperable, and they are difficult to diagnose.