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Basilea - Fosmanogepix acquired

Updated: Nov 20, 2023

Basilea announced this morning that it has entered into an asset purchase agreement with Amplyx Pharmaceuticals, a subsidiary of Pfizer, for the novel antifungal fosmanogepix. We believe that acquiring rights to fosmanogepix, which represents a truly exciting novel Phase 3 ready antifungal, represents a transformative event for the long-term future of the antifungal (and ultimately anti-infective) franchise at Basilea.

While Cresemba continues to be a very successful treatment for invasive fungal infections, we were concerned that exclusivity would likely wane in important markets of the US and Europe from 2027. Given that the vast majority of current profitability at Basilea is derived from the Cresemba franchise, the addition of fosmanogepix, along with the expected US approval of the 5th generation cephalosporin antibiotic ceftobiprole, effectively de-risks the long-term future of Basilea's anti-infective franchise,

The profile of fosmanogepix appears very attractive, with several important attributes. Fosmanogepix is highly selective and possesses good oral bioavailability. It exerts its anti-fungal properties by interfering with fungal cell wall synthesis, inhibiting Gwt1. Gwt1 is essential for mannoprotein-mediated fungal adhesion to mucosal and epithelial surfaces before colonisation. It appears to have a broad spectrum of activity against various Aspergillus and Candida, including those that are resistant to the echinocandins. The importance of fosmanogepix has been reflected in the FDA conferring Fast Track status for various invasive fungal infections, including invasive aspergillosis, candidiasis and mucormycosis. Fosmanogepix has already been studied extensively, which included three open-label phase 2 studies for the treatment of Candidemia, including Candida auris, and invasive mould infections. Data have been very promising, with activity against difficult-to-treat fungi and a good side effect profile suggesting that the Phase 3 programme has been substantially de-risked.

Basilea anticipates starting the Phase 3 programme in mid-2024, suggesting good visibility on the likely commercial profile before 2027. Importantly, Pfizer has retained first rights of negotiation for fosmanogepix after Phase 3 completion. Given the importance of the antifungal field to Pfizer (including certain rights to Cresemba), gained and its commercial prowess, we believe the ongoing interest represents an important endorsement of fosmanogepix and Basilea's expertise in developing novel anti-fungals.

Under the terms of the agreement, Basilea gains access to a preclinical anti-fungal programme and will pay $37m in upfront payments, as well as $110m in commercial milestone payments. Basilea has assumed all rights and obligations from previous agreements. Reflecting the costs associated with the transaction, the company has updated its 2023 financial guidance while confirming that it expects to remain profitable in both 2023 and 2024.

Our discounted cash flow fair valuation of CHF91 is now under review.

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Calvine Partners LLP is authorised and regulated by the Financial Conduct Authority.

Basilea Pharmaceutica is a client of Calvine Partners, and as such, this publication is not independent and should be considered a marketing communication under FCA Rules. None of the information in this publication should be considered as any form of advice.



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