In short
Tarperprumig (also known as ALXN1820) is an investigational protein-based medicine being developed by Alexion Pharmaceuticals. It is currently being studied in a Phase 2 clinical trial in adults with ANCA-associated vasculitis, a rare autoimmune disease. The trial is authorised and plans to enrol 75 participants. Tarperprumig works by blocking a protein called properdin, which is part of the complement system involved in this condition.
Key points
- Tarperprumig is an investigational medicine with no marketing authorisation in the product records.
- It is being studied in a Phase 2 trial for ANCA-associated vasculitis in adults.
- The authorised trial plans to enrol 75 participants.
- Tarperprumig is given as a subcutaneous injection.
- The trial compares tarperprumig with a placebo to assess safety and efficacy.
- The main measures are side effects and changes in safety assessments.
What is tarperprumig?
Tarperprumig (also known by its development code ALXN1820) is a protein-based substance developed by Alexion Pharmaceuticals, Inc. It is classified as a bispecific antibody and belongs to a group of medicines called anti-inflammatories and properdin inhibitors. The substance is still investigational: the product records show no marketing authorisation, meaning it has not yet been approved as a medicine for routine use. It has been given orphan drug status, which is a designation used to encourage the development of medicines for rare diseases.
How does tarperprumig work?
Tarperprumig works by blocking a protein called properdin, which is part of the body's natural defence system known as the complement system. The complement system normally helps protect the body against harmful invaders, but in people with ANCA-associated vasculitis it becomes activated in an unhelpful way and contributes to the disease. By inhibiting properdin, tarperprumig aims to reduce this harmful immune activity. The mechanism of action is recorded as properdin inhibition.
Which conditions is it used or studied for?
Tarperprumig is not yet authorised for any condition. It is being studied for one condition:
- ANCA-associated vasculitis — a rare autoimmune disease in which the immune system attacks small blood vessels, causing inflammation and damage. The current Phase 2 trial includes adults with newly diagnosed or relapsing ANCA-associated vasculitis.
An earlier Phase 1 study evaluated tarperprumig in healthy adults to understand its safety and how the body processes it.
How is tarperprumig given?
Tarperprumig is prepared as a solution for injection and is given by subcutaneous injection, meaning it is injected under the skin. In the Phase 2 trial, participants receive tarperprumig or a placebo by subcutaneous injection. The trial includes three study arms: tarperprumig every week, tarperprumig alternating weeks, or placebo.
What do the clinical trials show?
The clinical research on tarperprumig includes a completed Phase 1 study in healthy adults and an ongoing Phase 2 trial in people with ANCA-associated vasculitis. The Phase 2 trial is randomised, double-blind, and placebo-controlled, meaning participants are assigned by chance to receive either tarperprumig or a placebo, and neither they nor the researchers know which one they are getting. The trial is currently authorised and plans to enrol 75 participants.
The main measures in the Phase 2 trial are the number of side effects (called treatment-emergent adverse events, or TEAEs, and serious treatment-emergent adverse events, or TESAEs) and changes in safety assessments such as vital signs, physical examinations, laboratory tests, and electrocardiogram (ECG) results. The study also looks at pharmacokinetics (what the body does to the drug) and pharmacodynamics (what the drug does to the body). The trial has a screening period of up to 2 weeks, a treatment period of 52 weeks, and a safety follow-up period of 18 weeks.
The Phase 1 study in healthy adults assessed safety, tolerability, pharmacokinetics, pharmacodynamics, and immunogenicity (whether the body develops an immune response to the medicine).
What side effects are known?
The Phase 2 trial is specifically designed to measure the side effects of tarperprumig and how severe they are compared to placebo. The trial records list the incidence of treatment-emergent adverse events and serious treatment-emergent adverse events as primary outcome measures, but detailed side effect data from this trial are not yet available. Results from the earlier Phase 1 study in healthy adults are published, but the available source does not provide a specific list of side effects observed.