Felzartamab
An investigational treatment for IgA Nephropathy.
The same compound appears under different names depending on the context. Here is how to identify Felzartamab wherever you encounter it, plus the key facts at a glance.
- Generic name
- Felzartamab
- Development code
- MOR202
- Drug class
- Monoclonal antibody (anti-CD38)
- Manufacturer
- Biogen
- How it's taken
- Given as intravenous infusions.
An investigational antibody that removes plasma cells, the immune cells that make antibodies, including the faulty IgA behind IgA nephropathy. Phase 2 data showed lower urine protein that lasted after treatment stopped.
We'll email you when the FDA acts on Felzartamab and when new trials for IgA Nephropathy open. Unsubscribe anytime.
How Felzartamab works
Felzartamab is an antibody that targets and destroys plasma cells, which are immune cells producing harmful antibodies that cause kidney damage in IgA nephropathy. By reducing these cells, the drug helps prevent the autoimmune attack on your kidneys.
Mechanism: Fully human anti-CD38 monoclonal antibody that depletes pathogenic IgA-producing plasma cells
Side effects and safety
In the IGNAZ Phase 2a trial, the most common side effect was COVID-19, in 12 of 36 people on felzartamab and 3 of 12 on placebo, followed by colds and other upper respiratory infections. Non-serious infusion reactions were reported in 5 of 36 people in the main part of the trial, and 1 serious infusion reaction was reported. A few people had low white blood cell counts or low antibody levels, which may raise infection risk[4].
This is not a complete list of side effects. Talk to your doctor or pharmacist about what to expect and when to seek medical attention.
Taking Felzartamab
Given as intravenous infusions. In the Phase 2a study, patients received either 2, 5, or 9 doses over varying time periods. The Phase 3 PREVAIL trial, which started in May 2025, compares felzartamab infusions with placebo infusions.
Clinical trial results
In the IGNAZ Phase 2a trial with 54 patients, urine protein fell within 3 to 6 months. At 9 months it was down 29.5% with the 9-dose schedule versus 5.7% with placebo. With that schedule it was still down 44.5% at 24 months, 18 months after the 6-month treatment period ended[3]. The Phase 3 PREVAIL trial is enrolling about 454 patients[2]. Biogen is also testing felzartamab in 2 other Phase 3 trials outside IgA nephropathy: PROMINENT (NCT06962800), recruiting about 180 people with primary membranous nephropathy, and TRANSCEND (NCT06685757) in antibody-mediated kidney transplant rejection, which has finished enrolling 132 people.
Main registered trial: NCT06935357 on ClinicalTrials.gov. Check it for the current status, sites and contacts before asking about enrollment.
Development history
Felzartamab was first developed by MorphoSys. Human Immunology Biosciences (HI-Bio) licensed it, and Biogen acquired HI-Bio in July 2024 and now leads its development[1]. It is a fully human anti-CD38 antibody.
Explore IgA Nephropathy trials
Other IgA Nephropathy treatments
Common questions about Felzartamab
▸What is Felzartamab?
An investigational antibody that removes plasma cells, the immune cells that make antibodies, including the faulty IgA behind IgA nephropathy. Phase 2 data showed lower urine protein that lasted after treatment stopped.
▸How does Felzartamab work?
Felzartamab is an antibody that targets and destroys plasma cells, which are immune cells producing harmful antibodies that cause kidney damage in IgA nephropathy. By reducing these cells, the drug helps prevent the autoimmune attack on your kidneys.
▸What are the side effects of Felzartamab?
In the IGNAZ Phase 2a trial, the most common side effect was COVID-19, in 12 of 36 people on felzartamab and 3 of 12 on placebo, followed by colds and other upper respiratory infections. Non-serious infusion reactions were reported in 5 of 36 people in the main part of the trial, and 1 serious infusion reaction was reported. A few people had low white blood cell counts or low antibody levels, which may raise infection risk[4].
▸How is Felzartamab taken?
Given as intravenous infusions. In the Phase 2a study, patients received either 2, 5, or 9 doses over varying time periods. The Phase 3 PREVAIL trial, which started in May 2025, compares felzartamab infusions with placebo infusions.
▸Is Felzartamab FDA approved?
Felzartamab is currently in phase 3 clinical trials for IgA Nephropathy. It has not yet received FDA approval.
▸How does felzartamab differ from other IgAN treatments?
Felzartamab targets CD38 on plasma cells to remove the immune cells that make antibodies, including the faulty IgA, rather than blocking complement or cytokine pathways. No trial has compared it with other IgA nephropathy drugs.
▸What did the IGNAZ Phase 2a trial show?
In the IGNAZ trial with 54 patients, urine protein fell within 3 to 6 months, and with the 9-dose schedule it was down 29.5% at 9 months versus 5.7% on placebo. With that schedule, urine protein was still down 44.5% at 24 months, 18 months after the treatment period ended[3].
▸What is the current development status?
Felzartamab is in Phase 3 development. The PREVAIL trial (NCT06935357) started in May 2025 and plans to enroll about 454 patients to confirm the efficacy and safety seen in Phase 2[2].
▸What are anti-CD38 antibodies?
Anti-CD38 antibodies target and destroy cells expressing the CD38 protein on their surface, including plasma cells that produce antibodies. This class of drug is also used in multiple myeloma. Felzartamab is a fully human antibody that MorphoSys first tested in multiple myeloma and is now being studied in kidney diseases driven by the immune system[5].
▸Who is developing felzartamab?
Felzartamab was originally developed by MorphoSys under the code MOR202. Biogen gained it through its July 2024 acquisition of Human Immunology Biosciences (HI-Bio) and is advancing it for IgA nephropathy[1].
Sources and references
Every factual claim on this page is drawn from the public sources listed below. Click any reference to open the original document.
- Biogen · 2024-07-02. Biogen Completes Acquisition of Human Immunology Biosciences. https://investors.biogen.com/news-releases/news-release-details/biogen-completes-acquisition-human-immunology-biosciences
- ClinicalTrials.gov. PREVAIL: felzartamab in IgA nephropathy. https://clinicaltrials.gov/study/NCT06935357
- Kidney International (Floege J et al.) · 2025. Randomized, double-blind, placebo-controlled phase 2a study assessing the efficacy and safety of felzartamab for IgA nephropathy. https://pubmed.ncbi.nlm.nih.gov/40581166/
- ClinicalTrials.gov. IGNAZ: felzartamab (MOR202) in IgA nephropathy, posted results. https://clinicaltrials.gov/study/NCT05065970
- ClinicalTrials.gov. A Phase 1/2a Study of Human Anti-CD 38 Antibody MOR03087 (MOR202) in Relapsed/Refractory Multiple Myeloma. https://clinicaltrials.gov/study/NCT01421186