RLYB | Rallybio — Reverse Merger with Private Avenzo Therapeutics / June 1, 2026 / The M&A Hunter

Announced this morning. Rallybio acquires 100% of private Avenzo Therapeutics via reverse merger. Combined company rebrands as Avenzo Therapeutics, Inc. and trades on Nasdaq under AVZO. Expected close Q4 2026.

Ownership split tells the story. Pre-transaction RLYB shareholders retain roughly 2.8% of the combined entity on a treasury-stock-method basis, assuming Rallybio distributes its full pre-closing net cash before the deal closes. The remaining 97.2% flows to Avenzo stockholders and PIPE investors. Classic shell playbook.

RLYB holders receive two things: a cash distribution representing substantially all of Rallybio's pre-closing net cash, plus Contingent Value Rights tied to any net proceeds from the former REV102 program and other legacy assets. You get liquidity now, CVR optionality later, and a 2.8% stub in a well-capitalized oncology platform.

The $215 million PIPE was oversubscribed. Syndicate includes Blackstone Multi-Asset Investing, T. Rowe Price, Vivo Capital, Affinity, and ADAR1 as new investors alongside existing Avenzo backers — OrbiMed, SR One, Foresite, Surveyor, Longwood, NEA, Deep Track, Sands, Lilly Asia, and Sofinnova. Combined with existing cash, runway extends into late 2028 across multiple clinical readouts.

Avenzo brings four clinical-stage oncology programs: AVZO-021, a selective CDK2 inhibitor with updated Phase 1 data in HR+/HER2- breast cancer being presented at ASCO today; AVZO-023, a selective CDK4 inhibitor with preliminary fulvestrant combo data expected late 2026; AVZO-1418, an EGFR/HER3 bispecific ADC with updated Phase 1 data late 2026; and AVZO-103, a Nectin4/TROP2 bispecific ADC with initial Phase 1 data also late 2026. All four are U.S.-based small molecules or bispecific ADCs targeting solid tumors.

Dr. Athena Countouriotis leads the combined company as Chair, President and CEO. Dr. Mohammad Hirmand remains CMO. Avenzo's team runs the operation.

This is the second reverse merger Rallybio has pursued following the terminated Candid deal in May. The structure is identical in spirit: cash out the shell, bring in a well-funded private oncology asset, and reset the equity base. The PIPE quality here is institutional-grade and the CDK2/CDK4 angle puts AVZO directly into one of the most competitive and watched spaces in oncology. The ASCO data drop today on AVZO-021 is the first live test of the thesis.

Conference call is at 8:30 a.m. ET today.