Gilead Sciences is paying Knight Therapeutics $125 million in cash to buy the latter’s priority review voucher which can be used to speed up a future filing.

Introduced by the US Food and Drug Administration in September 2007, a PRV is an incentive for companies to invest in treatments for neglected tropical diseases. One of 16 tropical diseases that qualify is leishmaniasis, for which Knight’s Impavido (miltefosine) was approved in March by the FDA.

The Montreal-based group was also awarded a PRV which entitles the holder to a speedier review for a submission, from ten months down to six. Knight chief executive Jonathan Ross Goodman said in March that the company planned to “monetise the voucher for maximum value, which may take time to materialise”.

Eight months on, Knight has the money and the amount has surprised some observers, given that in August, Sanofi and Regeneron paid $67.5 million in August to buy a PRV from BioMarin for their new cholesterol drug, the PCSK9 inhibitor alirocumab.

Gilead has not disclosed what it intends to use the PRV for yet.