Genmab to acquire IBT portfolio company Merus

INTERNATIONAL BIOTECHNOLOGY TRUST PLC ("IBT")

Genmab agrees to acquire IBT portfolio company Merus

IBT notes the announcement this morning regarding Genmab's and Merus' transaction agreement, under which Genmab will acquire Merus for $97 per share in an all-cash transaction representing a transaction value of approximately $8.0 billion.

Merus is an oncology company developing innovative full-length human bispecific and trispecific antibody therapeutics, referred to as Multiclonics. Merus has a late-stage breakthrough therapy asset petosemtamab, currently in Phase 3 development. Genmab is an antibody-focused international biotechnology company with a 25-year track record.

This agreed offer represents a premium of approximately 41% over Merus' closing stock price on 26 September 2025. As at close of business on that date, Merus represents around 0.3% of IBT's Net Asset Value, as included in IBT's regular daily NAV update earlier this morning.

Commenting on the news, Ailsa Craig and Marek Poszepczynski, portfolio managers of IBT, said:

"Genmab's acquisition of Merus is IBT's 7th M&A deal for a holding in our portfolio so far this year, and our 32nd since 2020, again reiterating the benefit of IBT's investment strategy focusing on identifying potential acquisition targets, as large pharmaceutical companies use M&A to replenish their upcoming patent expiry pipelines. This deal again highlights how oncology is a key theme driving biotech returns, while helping improve the lives of millions of cancer patients each year.

"IBT's approach aims to pick potential M&A winners. While the timing of acquisition activity can be harder to predict, clusters of activity can be centred around key industry events as well as big pharma catching up with competitors' acquisition decisions. With three deals in IBT's portfolio in just over a week, we may be seeing a welcome flurry of activity, which has the potential to gain momentum."

The updated valuation of IBT's holding in Merus will be included in IBT's NAV as at close of business today, to be reported in the usual way tomorrow morning, 30 September.

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