Tiny Biotech Rallybio Stock Surges As $500 Million-Backed Merger Fuels Investor Optimism

Rallybio Corporation  (NASDAQ:RLYB) shares are up Monday following a merger agreement with Candid Therapeutics Inc.

This news has generated excitement among investors as the combined company aims to advance a leading portfolio of T-cell engager therapeutics for autoimmune diseases, adding momentum to the stock’s performance.

Merger

The merger will see Rallybio acquire Candid, which has secured over $505 million in financing from a syndicate of leading healthcare institutional investors. Pro-forma cash of approximately $700 million is expected to provide the combined company with a strong financial foundation.

The funding is expected to support operations through 2030, allowing the combined entity to push forward with multiple clinical milestones, including Phase 2 studies for its T-cell engager programs.

The transaction is anticipated to close in mid-2026, pending stockholder approval and regulatory conditions.

Following the merger, Rallybio equityholders are expected to own approximately 3.65% of the combined company, while Candid equityholders will hold around 96.35%.

Upon completion of the merger, the combined company expects to operate under the name Candid Therapeutics and trade on Nasdaq under the ticker symbol “CDRX”.

The broader market experienced declines on the previous trading day, with the Nasdaq down 1.40% and the S&P 500 falling 1.07%. This backdrop suggests that Rallybio’s gains are driven by company-specific news rather than broader market trends, as most sectors faced downward pressure.

RLYB Price Action: Rallybio shares were up 29.05% at $9.73 at the time of publication on Monday. The stock is trading at a new 52-week high.

Photo via Shutterstock