Rallybio (RLYB)
Develops rare-disease therapies while pursuing a merger with oncology developer Avenzo.
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Develops therapies for severe and rare diseases, focused on complement dysregulation and hematology. Without a commercial product, the clinical-stage company discontinued RLYB212 and has announced a merger that would pivot the combined business toward Avenzo's oncology pipeline.
Develops therapies for severe and rare diseases, centered on complement dysregulation and hematology. The clinical-stage company has no commercial product and discontinued the FNAIT program RLYB212 after pharmacokinetic data did not meet the stated efficacy threshold.
A collaboration with Momenta Pharmaceuticals, a Johnson & Johnson company, focused on complementary approaches for pregnant women at risk of FNAIT. The organization was founded by former Alexion executives and operates from New Haven, Connecticut.
An announced merger with Avenzo Therapeutics would shift the combined business toward Avenzo's oncology pipeline, subject to shareholder, registration, and other closing conditions. Clinical outcomes, partner and asset-disposition proceeds, and transaction conditions shape the business.
Company facts
No analyst consensus on record.
EPSReportedEstimate
RevenueReportedEstimate
Balance sheet, Jun 30, 2026Cash & short-term investments $92.8M · Total debt $0 · Total assets $98.1M · Shareholders' equity $94.5M
- Revenue
- $0
- Operating income
- −$5.7M
- Net income
- $43.7M
No dividends on record.
| Institutions38 holders · as of Mar 31, 2026 | 87.87% | 4.67M shares | |
| Insiders2 holders · as of Jul 10, 2026 | 0.20% | 10.7K shares | |
| Otherremainder | 11.93% | 633.4K shares |
5.31M company shares as of Sep 3, 2026 · institutions as of Mar 31, 2026 · holders as of their latest filing
A stock split fell inside the quarter, so quarter-on-quarter changes are not shown.
Top shareholders13F · 13D/G · Form 4
| Holder | Stake | Shares | Evidence |
|---|---|---|---|
FMR LLCInstitution | 14.94% | 793,451 | 13Fas of Mar 31, 2026 |
Viking Global Investors LPInstitution | 9.87% | 524,347 | 13Fas of Mar 31, 2026 |
Cormorant Asset Management, LPInstitution | 7.53% | 400,000 | 13Fas of Mar 31, 2026 |
TPG GP A, LLCInstitution | 7.13% | 378,551 | 13Fas of Mar 31, 2026 |
Balyasny Asset Management L.P.Institution | 7.09% | 376,573 | 13Fas of Mar 31, 2026 |
| See all 25 → | |||
13F — a manager's quarterly holdings
Insider tradesForm 4
| Date | Insider | Role | Shares | Avg price |
|---|---|---|---|---|
| May 18, 2026 | ADAR1 Capital Management, LLC | 10 percent owner | +6,009 | $13.98 |
| May 19, 2026 | ADAR1 Capital Management, LLC | 10 percent owner | +10,200 | $13.98 |
| May 13, 2026 | ADAR1 Capital Management, LLC | 10 percent owner | +79,259 | $13.99 |
| May 15, 2026 | ADAR1 Capital Management, LLC | 10 percent owner | +300 | $13.90 |
| May 11, 2026 | ADAR1 Capital Management, LLC | 10 percent owner | +50,000 | $14.00 |
- AstraZeneca (ADR)
Marketed C5 inhibitors for PNH and other complement diseases
- Regeneron
Phase 3 C5 combination development in PNH
- Novartis (ADR)
Oral alternative-pathway complement treatment for PNH
Compare
| Company | Price | Change | |||||
|---|---|---|---|---|---|---|---|
| Rallybio | $17.12 | +2.58% | $89.9M | 2.2 | — | 139.2 | 0.0% |
| AstraZeneca (ADR) | $164.32 | +1.65% | $250.67B | 24.3 | 15.2 | 4.1 | +6.4% |
| Regeneron | $845.50 | −0.77% | $87.78B | 21.1 | 14.1 | 5.7 | +16.7% |
| Novartis (ADR) | $161.75 | −0.42% | $308.79B | 24.5 | 17.3 | 5.6 | +0.9% |
| Median | 24.3 | 15.2 | 5.6 | +6.4% |