The Precision Immunology File
Merida Biosciences
The Cambridge biotech engineering antibody drugs that hunt down the antibodies making patients sick - and leave the healthy ones untouched.
- Company imagery
The Cambridge biotech engineering antibody drugs that hunt down the antibodies making patients sick - and leave the healthy ones untouched.
The immune system is supposed to defend you. In autoimmune and allergic disease, it turns the weapons inward - producing antibodies that attack the body's own tissue, or over-react to things that were never a threat. For decades, the standard answer has been blunt: suppress the whole immune response and accept the collateral damage, from infection risk to organ toxicity. Merida Biosciences was built on a different premise - that you can remove only the antibodies causing harm, and leave the protective ones standing.
Founded in 2022 and seeded inside Third Rock Ventures, Merida spent roughly three years in relative quiet before stepping into public view in April 2025 with a $121 million Series A. The round was co-led by Bain Capital Life Sciences, BVF Partners and Third Rock Ventures, with GV and the Perceptive Xontogeny Venture Funds joining. It was one of the larger immunology launches of the year - a signal that investors are willing to underwrite a more selective approach to a stubborn class of disease.
"Precision therapy for autoimmune-driven diseases is now within reach."- Merida Biosciences
The company's headquarters at 500 Technology Square places it in the middle of Kendall Square, the dense Cambridge cluster that has produced a long list of antibody drugs. What Merida is attempting there is specific: not a single medicine, but a platform - a repeatable way to point the same mechanism at many different antibody-driven diseases.
Merida's platform produces what it calls Fc biotherapeutics - drug molecules built around the Fc fragment, the tail end of an antibody rather than the more familiar business end. Each molecule is engineered to do three things at once, and it is the combination, not any single step, that defines the approach.
A precisely engineered protein domain binds the disease-causing antibody with high selectivity - recognizing the specific pathogenic target while ignoring the protective antibodies the body still needs.
The Fc component routes the captured antibody to liver cells for degradation. It engages the FcgammaRIIB receptor rather than FcgammaRIIA, a choice designed to avoid the toxicity that immune complexes can cause.
By agonizing FcgammaRIIB, the molecule can inhibit B cells in an antigen-specific way - telling the immune system to stop producing new pathogenic antibodies, for durability that outlasts a single dose.
Source: Merida Biosciences, Science & Platform
Put plainly: find the bad antibody, escort it to the body's disposal system, and switch off the factory making more. Most existing autoimmune drugs do at most one of those - they block or broadly deplete. Merida is betting that doing all three, selectively, is what turns symptom management into durable control.
Merida has translated the platform into three disclosed programs, each aimed at a different antibody-driven disease. The lead has reached the clinic; the others are moving through the studies that precede a first-in-human trial.
A precision biologic against thyroid-stimulating hormone receptor autoantibodies in Graves' disease and thyroid eye disease. In the NEXUS Phase 1 study.
An engineered antibody to neutralize and eliminate IgE for allergic diseases - severe asthma, atopic dermatitis, urticaria and food allergy - with potential for less frequent dosing.
Designed to clear autoantibodies against the phospholipase A2 receptor in primary membranous nephropathy while preserving immunity and avoiding alkylating agents linked to cancer risk.
"Incredible science starts with incredible people."
The ultimate customers are patients with antibody-driven autoimmune and allergic conditions, and the clinicians who treat them. Graves' disease alone affects a large population and can drive thyroid eye disease; severe allergy spans asthma, eczema, chronic hives and food allergy; primary membranous nephropathy is a chronic kidney disease that, untreated, can progress toward failure. These are conditions where existing options often force a trade between efficacy and safety.
That trade is the problem Merida is trying to dissolve. Broad immunosuppressants and B-cell depleters can work, but they lower the whole immune system's guard. Some standard therapies for membranous nephropathy rely on alkylating agents associated with cancer risk. Plasma exchange and IVIG are non-specific and often temporary. In each case, the treatment doesn't distinguish between the antibodies causing disease and the ones keeping a patient safe.
Merida's differentiation is that distinction. Rather than turning down immunity globally, its molecules are engineered to recognize a specific pathogenic antibody, remove it, and quiet its source - an antigen-specific strategy meant to deliver deep, durable depletion without broad toxicity. As a preclinical and early-clinical company, Merida has no product revenue; its near-term stakeholders are trial patients, research collaborators and investors.
The company positions this as precision immunology: the same shift toward selectivity that reshaped oncology, applied to autoimmune and allergic disease. If the platform holds, a single engineered approach could be pointed at more than two dozen conditions - which is the real reason a syndicate of blue-chip life-science investors wrote a nine-figure check before a single approval.
Merida enters an active moment in immunology. A wave of companies is chasing more selective ways to modulate the immune system, and capital has followed. Merida's own launch arrived alongside raises from peers like Hillstar Bio and Bambusa Therapeutics, and amid large pharma bets such as Sanofi's deal for Dren Bio's bispecific antibody.
| Approach | How it acts | Trade-off Merida targets |
|---|---|---|
| Broad immunosuppressants | Dampen overall immune activity | Infection risk, systemic toxicity |
| B-cell depleters (e.g. rituximab) | Remove B cells broadly | Loss of protective immunity |
| FcRn inhibitors (e.g. argenx) | Lower total IgG antibody levels | Non-selective antibody reduction |
| Merida Fc biotherapeutics | Bind, clear & suppress specific antibodies | Selectivity + durability, aimed at less toxicity |
The competitive question is not whether selectivity is desirable - it plainly is - but whether Merida's engineered Fc molecules can deliver it in patients as cleanly as they do on the bench. That is what the NEXUS study and the programs behind it will test.
Merida is led by Adam Townsend, President and Chief Executive Officer, with Dario Gutierrez, Ph.D., as Founder and Chief Scientific Officer and Dodzie Sogah, Ph.D., as Chief Operating Officer. Gutierrez, who has more than 15 years in immunology and oncology drug discovery, helped launch the company as an entrepreneur-in-residence at Third Rock Ventures.
The scientific foundation traces to academic co-founders including Pierre Bruhns, Ph.D., Director of Research at the Pasteur Institute, and Mark Shlomchik, M.D., Ph.D., Professor of Immunology at the University of Pittsburgh, alongside advisors from UNC, Scripps Research and Leiden University Medical Center. The board is chaired by Third Rock's Reid Huber and includes John Maraganore, founding CEO of Alnylam Pharmaceuticals - a reminder that the people around the company have built durable biotechs before.
"To improve the lives of patients living with autoimmune and allergic diseases through a new class of biotherapeutics."- Merida Biosciences, on its mission
Merida is founded and seeded by Third Rock, with Dario Gutierrez leading the science as an entrepreneur-in-residence.
The executive team and Cambridge operations build out as the platform advances toward the clinic.
Merida emerges from stealth with a round co-led by Bain Capital Life Sciences, BVF Partners and Third Rock Ventures, joined by GV and PXV Funds.
MER511 enters the Phase 1 NEXUS study for Graves' disease and thyroid eye disease, while the IgE and PLA2R programs advance through IND-enabling work.
Merida's drugs are built from the Fc fragment - the tail of an antibody - rather than the recognition end most people picture.
Instead of just blocking bad antibodies, the molecules escort them to the liver to be broken down.
The science traces partly to the Pasteur Institute in Paris - the institution founded by Louis Pasteur himself.
It develops engineered Fc biotherapeutics that selectively bind and eliminate the disease-causing antibodies behind autoimmune and allergic diseases while preserving protective antibodies, targeting conditions like Graves' disease, allergy and membranous nephropathy.
Merida launched in April 2025 with a $121 million Series A, co-led by Bain Capital Life Sciences, BVF Partners and Third Rock Ventures, with GV and PXV Funds participating. It was originally seeded by Third Rock in 2022.
Adam Townsend is President and CEO. Dario Gutierrez, Ph.D., is Founder and Chief Scientific Officer, and Dodzie Sogah, Ph.D., is Chief Operating Officer.
Rather than broadly suppressing the immune system, its molecules do three things at once - bind pathogenic antibodies, route them to the liver for degradation via FcgammaRIIB, and inhibit the B cells that produce them - aiming at the root cause with less toxicity.
MER511, a precision biologic targeting thyroid-stimulating hormone receptor autoantibodies in Graves' disease and thyroid eye disease, is the lead program and is in a Phase 1 study called NEXUS.
Merida has not published a dedicated YouTube channel or product-demo video at the time of writing. For talks and coverage on the company and its science, these searches are the best current starting points: