argenx Acquires Forte Biosciences from Biotech Growth Trust Portfolio for $2.2 Billion at 40.5% Premium

argenx's Acquisition of Forte Biosciences Marks Another Milestone for Biotech Growth Trust

The Biotech Growth Trust plc confirmed on 28 July 2026 that argenx SE completed the acquisition of Forte Biosciences, Inc, following argenx's announcement on 27 July 2026. The transaction values Forte at roughly $2.2 billion, or $77 per share in cash. Forte accounted for 3.03% of BIOG's net asset value at the announcement date, and the acquisition will be incorporated into BIOG's NAV as of 27 July 2026, with the updated figures released on 28 July 2026.

The 40.5% premium over Forte's closing price on 24 July 2026 underscores argenx’s strategic intent to acquire this clinical-stage biotech company. BIOG originally invested in Forte during a confidential private placement in November 2024 at $5.552 per share. This acquisition highlights BIOG’s investment approach of targeting early-stage biotechnology companies with innovative therapeutic platforms prior to widespread market recognition. The timing and valuation reflect strong confidence in Forte’s technology and clinical advancements.

FB102, a Novel Anti-CD122 Antibody, Demonstrates Clinical Potential in Autoimmune Diseases

Forte Biosciences is focused on developing treatments for immunological disorders. Its lead candidate, FB102, is a first-in-class anti-CD122 antibody with potential applications in several autoimmune diseases. Recent clinical trials have shown compelling proof-of-concept results in vitiligo and coeliac disease, validating the anti-CD122 mechanism and likely influencing argenx’s acquisition decision.

Developing first-in-class therapies for autoimmune diseases represents a significant biotech opportunity. Vitiligo, impacting millions worldwide, and coeliac disease, triggered by gluten, both have limited treatment options. FB102’s demonstrated efficacy across these indications suggests broader therapeutic potential, aligning with argenx’s expertise in immune-mediated diseases and justifying the acquisition premium.

Eight Successful Portfolio Exits in 12 Months Enhance BIOG’s Shareholder Value

The Forte acquisition marks the eighth successful M&A exit for BIOG within the past year. Previous exits include Avidity Biosciences, Cidara Therapeutics, Amicus Therapeutics, Apellis Pharmaceuticals, Kalvista Pharmaceuticals, Esperion Therapeutics, Nuvalent, Inc., and AtaiBeckley Inc. This series of transactions highlights BIOG’s effective strategy in identifying companies attractive to larger pharmaceutical and biotech acquirers. The frequency of these deals reflects active consolidation in the biotech sector.

According to BIOG’s portfolio manager, these M&A outcomes have significantly contributed to the trust’s performance by enabling realisations at acquisition premiums, such as the 40.5% premium for Forte. OrbiMed, BIOG’s investment adviser, has successfully deployed early-stage capital into differentiated therapeutic platforms, generating returns and providing capital for new investments aligned with long-term objectives.

OrbiMed’s Expertise Facilitates Early Access to Innovative Biotech Opportunities

Geoff Hsu, Portfolio Manager at The Biotech Growth Trust, emphasized OrbiMed’s competitive advantage through its team of scientific, medical, and investment experts in sourcing early-stage biotech companies. OrbiMed was among a select group invited to participate in Forte’s November 2024 private placement, reflecting its strong reputation and relationships within the biotech investment community. This early access provides BIOG with visibility into promising technologies and management teams ahead of broader market awareness.

This investment approach combines deep scientific insight, clinical evaluation, and disciplined capital deployment before full market recognition. Forte’s focus on a novel immunological target (anti-CD122) at an early clinical stage exemplifies this strategy. The subsequent clinical success and acquisition at a premium validate BIOG’s investment thesis and demonstrate how specialist expertise can uncover value creation opportunities beyond generalist investor reach.

Impact of Forte Investment on BIOG’s Portfolio and Valuation

BIOG’s initial investment in Forte Biosciences at $5.552 per share in November 2024 has appreciated substantially with argenx’s acquisition at $77 per share in cash. Forte represented 3.03% of BIOG’s net asset value at the announcement, indicating a meaningful position within the portfolio. The transaction’s impact will be reflected in BIOG’s NAV as of 27 July 2026, with details disclosed on 28 July 2026.

This realisation enhances BIOG’s overall portfolio performance and provides capital for redeployment into new opportunities. Shareholders should review the NAV update on 28 July 2026 to understand the precise financial contribution of the Forte exit and its effect on portfolio allocation.

Biotech M&A Activity Highlights Ongoing Consolidation in Immune-Mediated Disease Sector

argenx’s acquisition of Forte Biosciences aligns with broader biotech M&A trends, particularly in immune-mediated diseases. Larger pharma and biotech companies are actively acquiring smaller innovators to strengthen pipelines with differentiated therapies. BIOG’s eight M&A exits in 12 months underscore this consolidation trend. The $2.2 billion Forte deal reflects argenx’s strategic investment in advancing its immune disease portfolio through clinical-stage assets with validated proof-of-concept data.

Strong M&A activity supports BIOG’s investment thesis that companies developing first-in-class or best-in-class therapies for significant patient populations attract premium acquisition interest. The 40.5% premium paid by argenx signals high valuation multiples for promising biotech platforms, incentivizing venture capital and specialized investors to fund early-stage companies with potential for substantial clinical validation and acquisition.

Portfolio Strategy Drives Long-Term Value via Early-Stage Biotech Investments

The pattern of successful M&A exits over the past year demonstrates BIOG’s ability to create long-term shareholder value through early-stage biotech investing. The trust’s focus on small and mid-cap companies developing differentiated therapies has generated multiple premium acquisition outcomes. Portfolio manager commentary highlights how this strategy delivers substantial returns by identifying innovative biotech firms poised for strategic acquisition.

For investors, this performance indicates that BIOG’s selection process, supported by OrbiMed’s scientific and medical expertise, effectively targets companies likely to attract strategic buyers. This approach enhances the probability of liquidity events at premium valuations, mitigating risks associated with early-stage biotech investing. The portfolio’s diversification across multiple promising companies reduces concentration risk while maximizing return potential.

NAV Update on 28 July 2026 to Detail Financial Impact for Shareholders

The Biotech Growth Trust confirmed that the Forte acquisition will be included in its net asset value as of 27 July 2026, with the updated NAV published on 28 July 2026. This ensures shareholders receive timely and transparent information about the financial impact of this significant portfolio exit. The NAV announcement will detail Forte’s contribution to overall asset value and any related portfolio capital reallocations.

Investors should monitor the official NAV release on 28 July 2026 to assess the exit’s quantified effect on BIOG’s net asset value and performance metrics. The clear timeline for disclosure supports investor confidence in the trust’s valuation process and commitment to transparency regarding material portfolio events.

Investment Risks and Market Factors Affecting Biotech Growth Trust Portfolio

While the Forte acquisition represents a successful realisation for BIOG, early-stage biotech investing carries inherent risks. Clinical-stage programmes face regulatory uncertainties, and positive proof-of-concept data does not guarantee success in pivotal trials or regulatory approvals. Although FB102 showed encouraging results in vitiligo and coeliac disease, specific efficacy, safety, and regulatory timelines were not disclosed. Acquisition at a premium does not ensure future commercial success.

Additionally, biotech M&A activity and valuation multiples depend on broader market conditions, interest rates, and investor sentiment toward biotech equities. BIOG’s eight acquisitions in 12 months may reflect particularly favorable market dynamics. Future realisations may differ in premium levels or timing due to evolving market factors. Shareholders should recognize that past exit performance does not guarantee similar outcomes for remaining holdings. Maintaining portfolio diversification and disciplined capital redeployment remain critical risk management strategies.