Pharmaxis US licensee Chiesi files resubmission for Bronchitol with FDA, sets clock ticking for potential launch and US$10 million cash milestone

Pharmaxis Ltd (ASX:PXS) (OTCMKTS:PXSLY) (FRA:UUD) US licensee Chiesi Farmaceutici SpA has filed a resubmission that addresses issues raised by the US Food and Drug Administration (FDA) in a complete response letter received in June 2019 to the Bronchitol® New Drug Application (NDA).

The resubmission follows completion by Chiesi Group of a supplemental human factor study in the first quarter of 2020.

If Bronchitol is approved by the FDA, Pharmaxis will receive a US$10 million (A$15.5 million) milestone payment on the supply of Bronchitol for the US commercial launch and mid to high teen percentage royalties on in-market net sales.

Significant body of data

This study by the international research-focused healthcare group was the most significant body of additional data required by the FDA.

Pharmaxis CEO Gary Phillips said, “I’m delighted that the additional steps requested by the FDA in their complete response letter have been completed.

“We remain in close contact with our partner Chiesi Group and have supported them in this final step of the Bronchitol NDA where appropriate.”

The proposed indication for Bronchitol is management of cystic fibrosis to improve pulmonary function in patients 18 years of age and older in conjunction with standard therapies.

FDA’s review of the Bronchitol NDA is expected to be completed in mid-2020.

Response letter requirements

The complete response letter required Chiesi Group to revise product packaging and user instructions for Bronchitol and then conduct a supplemental human factor study demonstrating that the revisions would enable healthcare professionals to accurately and reliably administer the mannitol tolerance test.

This protocol, which incorporated advice and recommendations from the FDA, involved testing 45 healthcare professionals in settings simulating a typical mannitol tolerance test environment.

Gary Phillips said: “We anticipate that the FDA will complete its review in mid-year 2020 and that, if approved, Bronchitol will be made available for US adult CF patients in Q4 of 2020.

“Steps to prepare our Sydney manufacturing facility to meet US market requirements are already in hand.”

Chiesi is US licensee

Chiesi Group is responsible for the regulatory approval and commercialisation of Bronchitol in the United States.

Pharmaxis will manufacture and be the exclusive supplier of Bronchitol for the US market.

Bronchitol is approved and marketed in Europe, Russia, Australia and several other countries.

Story by ProactiveInvestors