FDA Grants AML Drug Volasertib Orphan Drug Designation

Boehringer Ingelheim announced in April that its new drug volasertib has been granted orphan drug designation by both the US Food and Drug Administration and by the European Medicines Agency. Volasertib is in trials for the treatment of patients with acute myeloid leukemia (AML).

Volasertib was granted Breakthrough Therapy Designation last year by the FDA, which allows for potentially accelerated approval for drugs that treat difficult diseases and conditions. The new orphan designation also lends support to the testing and authorization process, specifically for drugs that treat rare diseases. In the case of AML, this is related to the fact that many patients do not respond well to standard chemotherapy, and may not be candidates for such treatments in the first place.

“Due to the targeted way in which volasertib works, we hope it will offer a new alternative for those patients who are currently left with limited options,” said Klaus Dugi, MD, the chief medical officer at Boehringer Ingelheim, in a press release.

The drug is a selective inhibitor of Polo-like kinase 1 (Plk1); blocking this enzyme eventually leads to cell death, and ideally would slow the rapid division of cells in AML. It has been tested in several malignancies; one phase II trial in patients with advanced or metastatic urothelial cancer showed insufficient antitumor activity to continue the research.

In AML, however, early results were promising with volasertib. A phase II study whose results were presented late in 2012 showed higher objective response rates in patients who received volasertib along with low-dose cytarabine compared with cytarabine alone. There was also a trend toward longer event-free survival with the combination; the study was conducted in patients newly diagnosed with AML who were considered ineligible for intensive chemotherapy.

That study led to an ongoing phase III trial known as POLO-AML-2. Again, that trial will include patients with previously untreated AML who are ineligible for intensive remission induction therapy, and will again combine volasertib with cytarabine. The study’s estimated enrollment is 660 patients, all of whom will be at least 65 years of age; the average age of AML patients in general is between 65 and 70 years.