CLINICAL TRIALS PROFILE FOR DACLIZUMAB

All Clinical Trials for daclizumab

Trial ID	Title	Status	Sponsor	Phase	Start Date	Summary
NCT00001526 ↗	ANTI-TAC THERAPY FOR UVEITIS	Completed	National Eye Institute (NEI)	Phase 1	1996-06-04	Uveitis refers to intraocular inflammatory diseases that are an important cause of visual loss. Standard systemic immunosuppressive medications for uveitis can cause significant adverse effects. Consequently, an effective treatment with a safer side effect profile is highly desirable. This pilot study has permitted enrollment of up to 12 adults with non-infectious intermediate or posterior uveitis who require treatments to maintain visual function. This extended protocol began with an evaluation of the safety and potential efficacy of intravenous (IV) daclizumab treatments for uveitis while reducing or eliminating standard medications commensurate with the standard of care. As subcutaneous (SC) daclizumab treatments become available, eligible participants will be offered continuing daclizumab treatments using the new SC formulation, though they may elect to remain on the IV treatments. If the therapeutic benefit is sustained using the SC formulation, maintenance therapy will continue as clinically indicated. Participants who repeatedly fail the SC therapy will be permitted to revert to the IV daclizumab regimen they previously used, or may exit the study as treatment failures. SC treatments begin with a short SC induction at 2 mg/kg followed by 1 mg/kg treatments on a 4-week schedule as the protocol originally specified. Participants will be monitored routinely when each dose is received and additionally will participate in pharmacokinetic studies to monitor SC formulation bioavailability. Daclizumab is a humanized anti-Tac monoclonal antibody (HAT, Zenapax) that interferes with inflammatory processes by its involvement with the interleukin 2 receptor (IL-2R). During the first 5 years of this study, only an IV product was available. The SC formulation is now available containing the same daclizumab drug product. Preliminary studies indicate that the SC formulation is well tolerated by normal control subjects and other autoimmune disease patients at repeated doses up to 2 mg/kg. The primary objectives are to examine the safety and potential efficacy of IV and later, SC daclizumab, while continuing to reduce other immunosuppressive medications commensurate with the standard of care. Primary safety outcomes are the discontinuation of study therapy due to reduced vision or the occurrence of adverse events. Secondary outcome measures include visual acuity and the grading of immunosuppressive medications, anterior chamber and vitreous cells, and vitreous haze.
NCT00001865 ↗	HAT in Eye Complications of Behcet's Disease	Completed	National Eye Institute (NEI)	Phase 2	1999-07-01	This study will evaluate the safety and effectiveness of Zenapax in controlling recurrent eye inflammations associated with Behcet's disease. Behcet's disease is usually treated with corticosteroids to suppress inflammation. Other medicines such as methotrexate, cyclophosphamide, or azathioprine may also be used. These drugs all can have serious side effects, including liver or kidney damage. Zenapax is a monoclonal antibody that binds to certain proteins (receptors) on white blood cells, preventing them from interacting with a chemical called interleukin-2. Blocking this interaction prevents inflammation. This study will include 20 patients who had unacceptable side effects from other medicines used to treat their disease; did not benefit from standard treatment; and refused standard treatment because of possible side effects of the medicines. All patients in the study will continue to take their current medicines at the start of the study. In addition, one group of patients will receive Zenapax and a second group will receive a placebo. The drug or placebo will be infused into the vein at the start of the study and every two weeks for the next six weeks, and then every four weeks for the rest of the study period (24 months). Each infusion lasts about 15 minutes. Patients will have eye examinations at the time of every treatment, and medicines will be added if needed to control eye disease. Drugs will be tapered after six months in patients whose eye disease is quiet, and readjusted as necessary. Neither the doctors nor the patients will know who is receiving placebo and who is receiving Zenapax until the study ends. Patients will be given a physical examination, medical history, eye examination, fluorescein angiography (special photographs of the retina to evaluate the blood vessels in the eye), and blood tests. Zenapax was previously studied in 10 patients with uveitis with positive results. The patients were able to reduce the other medicines they were taking with minimal side effects.
NCT00001962 ↗	A Study to Determine Whether Therapy With Daclizumab Will Benefit Patients With Bone Marrow Failure	Terminated	National Heart, Lung, and Blood Institute (NHLBI)	Phase 2	1999-11-01	Participants in this study are suffering from rare and serious blood disorders. In aplastic anemia, the bone marrow stops producing red blood cells, platelets, and white blood cells. In pure red cell aplasia, the bone marrow stops producing red cells, and in amegakaryocytic thrombocytopenic purpura, the bone marrow stops producing platelets. Current treatment approaches for these disorders include bone marrow transplant and/or immunosuppression. However, bone marrow transplant is not always possible, and immunosuppression has serious side effects. This study will investigate whether daclizumab can be used to treat these disorders. Daclizumab is a genetically engineered human antibody that blocks the interleukin-2 receptor on immune cells. It has been used successfully in many transplant patients to reduce the rate of organ rejection. Participants will undergo a complete history and physical examination. A bone marrow aspiration and biopsy will be performed to confirm the type of bone marrow failure. About 5 tablespoons of blood will be drawn for baseline tests and research purposes. Daclizumab will be administered every 2 weeks by vein in a 30-minute infusion. The first dose will be given at NIH and the next four may be given at NIH or by the participant's primary hematologist. The treatment will last 8 weeks. Participants must also see their referring physician or NIH physicians every 2 weeks for blood counts. In the fourth and eighth weeks of the study and at the 3-month follow-up visit, 2 tablespoons of blood will be drawn at NIH. At the 1-month follow-up visit to NIH, 5 tablespoons of blood will be drawn and another bone marrow aspiration and biopsy performed. Risks from bone marrow aspiration and biopsy and blood draws include discomfort. Daclizumab is usually well-tolerated; however, it may weaken immunity against certain bacteria and viruses.
NCT00001962 ↗	A Study to Determine Whether Therapy With Daclizumab Will Benefit Patients With Bone Marrow Failure	Terminated	Neal Young, M.D.	Phase 2	1999-11-01	Participants in this study are suffering from rare and serious blood disorders. In aplastic anemia, the bone marrow stops producing red blood cells, platelets, and white blood cells. In pure red cell aplasia, the bone marrow stops producing red cells, and in amegakaryocytic thrombocytopenic purpura, the bone marrow stops producing platelets. Current treatment approaches for these disorders include bone marrow transplant and/or immunosuppression. However, bone marrow transplant is not always possible, and immunosuppression has serious side effects. This study will investigate whether daclizumab can be used to treat these disorders. Daclizumab is a genetically engineered human antibody that blocks the interleukin-2 receptor on immune cells. It has been used successfully in many transplant patients to reduce the rate of organ rejection. Participants will undergo a complete history and physical examination. A bone marrow aspiration and biopsy will be performed to confirm the type of bone marrow failure. About 5 tablespoons of blood will be drawn for baseline tests and research purposes. Daclizumab will be administered every 2 weeks by vein in a 30-minute infusion. The first dose will be given at NIH and the next four may be given at NIH or by the participant's primary hematologist. The treatment will last 8 weeks. Participants must also see their referring physician or NIH physicians every 2 weeks for blood counts. In the fourth and eighth weeks of the study and at the 3-month follow-up visit, 2 tablespoons of blood will be drawn at NIH. At the 1-month follow-up visit to NIH, 5 tablespoons of blood will be drawn and another bone marrow aspiration and biopsy performed. Risks from bone marrow aspiration and biopsy and blood draws include discomfort. Daclizumab is usually well-tolerated; however, it may weaken immunity against certain bacteria and viruses.
NCT00006350 ↗	Mycophenolate Mofetil, Tacrolimus, Daclizumab, and Donor Peripheral Stem Cell Transplantation in Treating Patients With Hematologic Cancer	Completed	University of Maryland Greenebaum Cancer Center	Phase 2	2000-01-01	RATIONALE: Monoclonal antibodies such as daclizumab can locate tumor cells and either kill them or deliver tumor-killing substances to them without harming normal cells. Peripheral stem cell transplantation from a brother or sister may be effective treatment for hematologic cancer. Sometimes the transplanted cells can be rejected by the body's tissue. Mycophenolate mofetil, tacrolimus, and donor white blood cells may prevent this from happening. PURPOSE: Phase II trial to study the effectiveness of mycophenolate mofetil, tacrolimus, daclizumab, and donor peripheral stem cell transplantation in treating patients who have hematologic cancer.

Clinical Trial Conditions for daclizumab

Condition Name

Condition Name for daclizumab
Intervention	Trials
Kidney Transplantation	10
Uveitis	6
Relapsing-Remitting Multiple Sclerosis	5
Liver Transplantation	5

Condition MeSH

Condition MeSH for daclizumab
Intervention	Trials
Diabetes Mellitus	13
Diabetes Mellitus, Type 1	13
Multiple Sclerosis	9
Sclerosis	9

Clinical Trial Locations for daclizumab

Trials by Country

Trials by Country for daclizumab
Location	Trials
United States	255
Poland	34
Germany	29
Canada	28
France	24

Trials by US State

Trials by US State for daclizumab
Location	Trials
Maryland	29
Florida	22
California	13
New York	12
Texas	12

Clinical Trial Progress for daclizumab

Clinical Trial Phase

Clinical Trial Phase for daclizumab
Clinical Trial Phase	Trials
Phase 4	21
Phase 3	17
Phase 2/Phase 3	1

Clinical Trial Status

Clinical Trial Status for daclizumab
Clinical Trial Phase	Trials
Completed	74
Terminated	8
Withdrawn	4

Clinical Trial Sponsors for daclizumab

Sponsor Name

Sponsor Name for daclizumab
Sponsor	Trials
National Institute of Allergy and Infectious Diseases (NIAID)	11
Hoffmann-La Roche	11
National Eye Institute (NEI)	9

Sponsor Type

Sponsor Type for daclizumab
Sponsor	Trials
Other	93
Industry	51
NIH	42

Daclizumab: Clinical Trial Status Update, Market Analysis, and Projection

Last updated: April 25, 2026

What is daclizumab’s current clinical and regulatory status?

Daclizumab (marketed in the US as Zinbryta) is withdrawn from the market and not in active late-stage development as a standalone therapy for its original approved indications.

Regulatory trajectory (US/EU)

• US (FDA):
  • Zinbryta (daclizumab) was withdrawn from the market following safety concerns (cases of severe immune-mediated adverse events, including encephalitis and hepatitis). The FDA issued the withdrawal decision and associated safety communications.
  • Source: FDA withdrawal notice and safety communications for Zinbryta. [1][2]
• EU/EMA:
  • European safety reviews and restrictions culminated in further regulatory actions; the drug was removed from routine use in practice after the same risk signal.
  • Source: EMA product/safety communications. [3]

Clinical development footprint after withdrawal

• Daclizumab’s development history for multiple sclerosis included randomized, controlled programs and long-term extension studies that informed approval and labeling.
• After market withdrawal, new pivotal trials were not sustained at scale for the original product program, and the commercialization path shifted away from daclizumab in MS.
• Source set includes FDA and EMA materials describing withdrawal context and the controlled clinical evidence base. [1][2][3]

What were the key efficacy and safety characteristics behind approval?

Daclizumab targeted CD25 (IL-2 receptor alpha chain), modulating T-cell activation.

Efficacy benchmark (clinical context of approval)

• Controlled trials established reductions in disease activity in relapsing forms of MS versus comparators, using MRI lesion burden and relapse metrics.
• Source: FDA medical review and trial summaries used to support approval. [1]

Safety profile that drove withdrawal

• The withdrawal was driven by serious immune-mediated adverse events that emerged in post-marketing and broader safety surveillance, including:
  • Severe hepatic injury
  • Encephalitis
  • Other immune-mediated events consistent with CD25 pathway modulation risks
• Source: FDA withdrawal/safety communications and review materials. [1][2]

What is the current market reality for daclizumab?

Commercial status

• Zinbryta is no longer a marketed product in the US, and commercial access in other regions is also constrained by regulatory actions and withdrawals.
• The market is therefore best characterized as post-withdrawal with minimal to no new demand.

Market implications of withdrawal

• Revenue exposure is limited to:
  • Residual supply chains (if any) before full withdrawal completion
  • Pre-existing patient treatment continuity where regulators allowed wind-down (typically short)
  • Any off-label use where legally possible (but broadly constrained by risk posture and availability)
• In practice, investment-grade market modeling for daclizumab itself trends toward declining to near-zero net sales after withdrawal.

Competitive landscape

• Multiple sclerosis immunology is now dominated by:
  • Anti-integrin therapies (e.g., natalizumab)
  • S1P modulators (e.g., fingolimod-class; multiple entrants)
  • Monoclonal antibodies targeting other immune checkpoints and trafficking pathways
  • CD25-axis programs are now evaluated with much tighter safety expectations after the daclizumab signal
• For a market projection tied to daclizumab, competitive substitution is the decisive variable: treatment demand shifts to other mechanisms rather than to daclizumab.

What does a market projection look like for daclizumab?

Given the regulatory withdrawal, the projection is structurally tied to product availability and treatment substitution, not to new clinical entrants.

Base case projection (conceptual, product-specific)

• Near-term (0-2 years): net sales remain at very low levels if any supply persists, with declining patient numbers due to discontinuation.
• Mid-term (3-5 years): net sales approach near-zero because active prescribing is effectively eliminated by withdrawal and safety posture.
• Longer term: daclizumab brand remains primarily relevant to historical data and pharmacovigilance learnings rather than ongoing revenue.

Scenario framing tied to regulatory constraints

• Bull case: limited patient wind-down and localized access before full cessation; does not reverse underlying withdrawal.
• Bear case: faster discontinuation plus stronger enforcement against reinitiation; accelerates the sales drop.

Because the product is withdrawn, these scenarios compress toward the same endpoint: minimal remaining commercial viability for daclizumab as a branded therapy.

What clinical research remains relevant: residual data vs new programs?

Daclizumab continues to matter for:

• Long-term safety characterization and pharmacovigilance
• Mechanism-of-action learning for IL-2 pathway modulation
• Development of next-generation immunology strategies that avoid the same risk profile

But the operating assumption for market projection remains anchored to: withdrawal eliminates the commercial engine.

How should R&D stakeholders position daclizumab learnings for future programs?

Even though daclizumab is withdrawn, CD25 biology still influences development choices. Key downstream implications for later programs include:

• Tighter immune monitoring
• More conservative risk-benefit thresholds
• Trial designs that detect liver and CNS immune-mediated signals earlier
• Clear stopping rules for immune-mediated adverse events

These program design lessons are a direct translation of the withdrawal rationale described by regulators. [1][2]

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Key Takeaways

• Daclizumab (Zinbryta) is withdrawn in the US following serious immune-mediated safety events; the core clinical basis for approval is outweighed by the risk signal. [1][2]
• EMA regulatory actions align with the post-approval safety concerns and restrict routine use. [3]
• The product’s market projection trends to near-zero because withdrawal stops new commercial demand and accelerates discontinuation.
• Daclizumab is now a reference point for CD25/IL-2 pathway risk management in future immunology R&D rather than a growth opportunity.

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FAQs

1) Is daclizumab currently available for new MS prescriptions?

No. Zinbryta is withdrawn from the US market following safety-related regulatory action. [1][2]

2) What safety events drove the withdrawal?

Severe immune-mediated adverse events, including encephalitis and hepatitis/liver injury, were central to the regulatory decision. [1][2]

3) What was daclizumab’s mechanism of action?

It targets CD25 (IL-2 receptor alpha chain) to modulate T-cell activation. [1]

4) Does daclizumab have active late-stage development now?

Not as a revived pivotal program in the original MS indication; withdrawal shifted focus away from sustained commercialization and new large late-stage trials. [1][2][3]

5) How does this affect investment and partnering?

Market upside is constrained because regulatory withdrawal eliminates a normal revenue ramp; daclizumab’s value is mainly in safety/biological learning for subsequent programs. [1][2]

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References (APA)

[1] U.S. Food and Drug Administration. (2018). FDA drug safety communication: FDA approves withdrawal of Zinbryta (daclizumab) from the market (safety communication and related materials). https://www.fda.gov/
[2] U.S. Food and Drug Administration. (2018). Zinbryta (daclizumab) information and safety-related communications. https://www.fda.gov/
[3] European Medicines Agency. (2018). EMA safety communications and regulatory actions for Zinbryta (daclizumab). https://www.ema.europa.eu/