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Basilea adds another antibiotic programme

Continuing its successful efforts to refill the anti-infective pipeline with new programmes, which have included the transformational addition of the novel clinical stage anti-fungal fosmanogepix and the novel clinical stage antibiotic tonabacase, Basilea has announced this morning that it has entered into an asset purchase agreement with Spexis AG regarding its programme targeting Gram-negative bacteria (including MDR strains). Many problematic bacteria, 4 out of 6 of the critical ESKAPE pathogens, are Gram-negative. The increasing threat of resistance has resulted in the WHO publishing a priority list of concerning bacteria, including the Gram-negative pathogens Pseudomonas aeruginosa, Acinetobacter baumannii, and Enterobacteriaceae species as the highest priority. As a result, the development of effective and safe antibiotics to treat Gram-negative infections remains a key objective, although success here generally has been poor.

The Spexis AG approach has been to target the lipopolysaccharide (LPS) bridge developing novel candidates using its OMPTA (outer membrane protein targeting antibiotics) programme. Given its importance to the integrity of the cell membrane, effectively blocking antibiotic entry and protecting Gram-negative bacteria, LPS has proven to be a popular and effective target for established (but effectively last resort) Gram-negative antibiotics such as the polymixins and colistin. The objective of the OMPTA platform antibiotics has been to internalise LPS, compromising the cell membrane and resulting in bacterial cell death. Data generated to date have been encouraging, with good activity against important target pathogens such as the Enterobacteriaceae, as well as resistant strains (including colistin resistance). The importance of the OMPTA programme has been reflected in the award of funding from CARB-X to aid development, which focuses on accelerating programmes targeting the WHO and CDC's priority list pathogens.

Under the terms of this agreement, Basilea is acquiring all the OMPTA compounds, including know-how and IP, for the relatively modest sum of up to CHF 2m, which includes a potential final milestone payment "...related to the availability of near-term external funding for the further development of the programme".

While still early stage, the addition of this OMPTA programme represents a highly innovative approach targeting priority pathogens with signficant clinical and commercial potential. It also neatly fills a gap in the antibiotic pipeline at Basilea targeting Gram-negative bacteria. In the near term and with respect to the antibiotic franchise, all eyes are on the antibiotic ceftobiprole, which is approaching its FDA action date (April 3rd 2024) and the attraction of a relevant commercial partner before approval.

Following the recent in-licensing and acquisition activities, our previous discounted cash flow fair value of CHF91 is 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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