LEI: 549300Q7EXQQH6KF7Z84

19 August 2026

RTW Biotech Opportunities Ltd

BioMarin to acquire Alesta Therapeutics

·      Upfront cash payment of $275 million for lead asset ALE1 represents 41% uplift to 31 July carrying value

·      Further milestone payments for ALE1 of up to $215 million; other assets to be spun out to a new entity

·      Sixth M&A transaction in RTW Bio's portfolio in 2026

RTW Biotech Opportunities Ltd ("RTW Bio" or "the Company"), the London Stock Exchange-listed investment company focused on identifying transformative assets with high growth potential across the life sciences sector, is pleased to note the announcement by BioMarin Pharmaceutical Inc. ("BioMarin", Nasdaq: BMRN) that it has entered into a definitive agreement to acquire private portfolio company Alesta Therapeutics ("Alesta").

Alesta is a clinical-stage biotechnology company developing novel oral small-molecule therapies for underserved rare diseases. Its lead asset, ALE1, is in development for hypophosphatasia, a rare inherited disease that impairs bone and tooth mineralisation and can cause fractures, tooth loss, muscle weakness, fatigue and pain.

Under the terms of the agreement, BioMarin will pay up to $490 million ($275 million in upfront cash and Alesta shareholders may receive up to a further $215 million upon achievement of certain milestones) for ALE1. Immediately prior to close, Alesta will spin out all non-ALE1 assets to a newly-formed entity, in which existing Alesta shareholders, including RTW Bio, will retain their pro rata interest. The transaction is expected to close in the third quarter of 2026.

RTW Bio first invested in Alesta's Series A financing in December 2024 and again in September 2025, investing €2.4 million in aggregate. As at 31 July 2026, RTW Bio's holding in Alesta was valued at $3.8 million, representing 0.4% of the Company's NAV. The upfront cash payment of $275 million (net of closing adjustments) for ALE1 represents an estimated 41% uplift on the Company's carrying value of Alesta, adding $1.6 million (+0.2%) to the 31 July NAV.

This is the sixth acquisition from RTW Bio's portfolio announced in 2026, following Boston Scientific's acquisition of Penumbra, GSK's acquisition of RAPT Therapeutics, Biogen's acquisition of Apellis Pharmaceuticals, Eli Lilly's acquisition of Centessa Pharmaceuticals and AbbVie's acquisition of Apogee Therapeutics.

Rod Wong, CIO of RTW Investments, said, "We backed Alesta at Series A because of the differentiated profile of ALE1, supported by a management team with a strong track record in rare disease drug development. BioMarin's decision to acquire the company at pre-Phase 2 data is a clear validation of our strategy of identifying and supporting differentiated science at the earliest stages of the private markets, where the greatest value can be created for our shareholders. This is the sixth acquisition from our portfolio announced this year and reflects continued strategic appetite from large-cap pharma facing a cumulative $170 billion patent cliff by 2032. We expect the current pace of dealmaking to persist, and RTW Bio remains well positioned across both its public and private portfolios to benefit."

The announcement can be found here.

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About RTW Biotech Opportunities Ltd:

RTW Biotech Opportunities Ltd (LSE: RTW) is an investment fund focused on identifying transformative assets with high growth potential across the biopharmaceutical and medical technology sectors. Driven by a long-term approach to support innovative businesses, RTW Biotech Opportunities Ltd invests in companies developing next-generation therapies and technologies that can significantly improve patients' lives. RTW Biotech Opportunities Ltd is managed by RTW Investments, LP, a leading healthcare-focused entrepreneurial investment firm with deep scientific expertise and a strong track record of supporting companies developing life-changing therapies.

Visit the website at www.rtwbio.com for more information.

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The information in this announcement may include forward-looking statements, which are based on the current expectations and projections about future events, and in certain cases can be identified by the use of terms such as "may", "will", "should", "expect", "anticipate", "project", "estimate", "intend", "continue", "target", "believe" (or the negatives thereon) or other variations thereon or comparable terminology. These forward-looking statements, as well as those included in any related materials, are subject to risks, uncertainties and assumptions about the Company and/or its underlying investments, including, among other things, the development of the applicable entity's business, trends in its operating industry, expected use of financing proceeds and future capital expenditures and acquisitions. In light of these risks, uncertainties and assumptions, the events in the forward-looking statements may not occur.