Argenx Expands Immunology Portfolio with $2.2B Buyout of Forte Biosciences
Argenx agreed to acquire Forte Biosciences for $2.2B to expand its immunology portfolio. The deal centers on Forte’s anti-CD122 antibody FB102, which showed Phase Ib vitiligo results with 29.6% mean FVASI improvement at week 24 (p=0.020). Argenx plans a $77 per share cash tender offer, expected to close in Q3.
How this was made

The 30-second read
Why it matters
The acquisition combines a defined $2.2B price, a $77 per-share cash tender offer with an ~86% premium to Forte’s post-data VWAP, and early clinical efficacy metrics that support the immunology portfolio expansion thesis.
Market read
Traders can act on deal-premium repricing, tender-spread dynamics, and closing-condition risk, with FB102’s early efficacy providing the fundamental valuation anchor.
What to watch
Closing is contingent on HSR and tender thresholds; any delay or adverse regulatory development could compress the deal spread and increase downside volatility for both ARGX and FBRX into Q3.
Background
Argenx previously held a strategic investment in Forte and is now moving to acquire it, citing FB102’s Phase Ib vitiligo and celiac disease data as key drivers.
Ticker impact
Argenx agreed to buy Forte Biosciences for $2.2B, including a $77 cash tender offer, to expand its immunology pipeline via FB102.
Likely continued volatility and upside bias while markets price in FB102 value and deal premium, tempered by deal-close risk into Q3.
The article discloses a specific $2.2B acquisition, $77 per share tender offer, premium vs VWAP, and the clinical efficacy datapoints that underpin the strategic rationale.
Forte Biosciences is the acquisition target, with its shares jumping about 40% on the $2.2B buyout and a $77 per-share cash tender offer.
Near-term strength likely persists, but price may track deal-spread dynamics and any emerging regulatory/HSR or closing-condition signals.
The article provides the tender offer price, premium magnitude, and key closing conditions (HSR waiting period and minimum tender threshold).
Market effects
Reinforces continued M&A appetite for immunology assets with early clinical efficacy, potentially supporting valuation expectations for similar-stage antibody programs.
European listing (Euronext Brussels) shows mild weakness for ARGX while Nasdaq ADRs fall, suggesting cross-venue positioning and FX/flow effects around the deal headline.
Large cross-border biotech deal can influence sentiment toward autoimmune immunology R&D pipelines and deal-making liquidity internationally.
Counterpoint
The premium may already be largely priced in, and FB102’s early Phase Ib signals may not translate into Phase II/III outcomes, limiting upside beyond deal mechanics.
Key entities
- companyArgenx
Acquirer of Forte Biosciences for $2.2B to expand immunology pipeline via FB102.
- companyForte Biosciences
Target company whose shares surged on the announced $77 cash tender offer and deal premium.
- assetFB102
Early clinical-stage anti-CD122 monoclonal antibody with Phase Ib vitiligo and prior celiac disease results cited as drivers.
- productVyvgart franchise
Argenx’s marketed immunology drugs (efgartigimod) referenced as the current blockbuster base supporting growth beyond peak.


