Garadacimab

Efgartigimod (efgartigimod alfa, brand names Vyvgart intravenous and Vyvgart Hytrulo subcutaneous) is a first-in-class antagonist of the neonatal Fc receptor (FcRn) developed by argenx as ARGX-113. It is not a small synthetic peptide but an engineered fragment of the human immunoglobulin G1 (IgG1) antibody - specifically the Fc portion that normally binds FcRn - modified with argenx's ABDEG technology to bind FcRn with much higher affinity than natural IgG at both neutral and acidic pH. FcRn is the salvage receptor that rescues circulating IgG from lysosomal degradation and recycles it back into the blood, giving antibodies their long half-life. By outcompeting endogenous IgG for FcRn, efgartigimod blocks that recycling and drives rapid clearance of IgG - including the pathogenic autoantibodies that cause many autoimmune diseases - typically lowering total IgG by roughly 60-70% within weeks, without reducing IgM, IgA, or albumin. It was the first FcRn blocker ever approved: FDA-approved in December 2021 (Vyvgart IV) for acetylcholine-receptor-antibody-positive generalized myasthenia gravis (gMG) on the strength of the Phase 3 ADAPT trial, followed by a subcutaneous co-formulation with recombinant hyaluronidase (Vyvgart Hytrulo) for gMG in 2023 and for chronic inflammatory demyelinating polyneuropathy (CIDP) in 2024. In May 2026 the FDA expanded the gMG label to all serotypes - including AChR-antibody-negative (seronegative) patients - based on the Phase 3 ADAPT SERON trial, making efgartigimod the first and only therapy approved across every gMG antibody subtype. It is being studied in a broad set of other IgG-driven autoimmune diseases, including primary immune thrombocytopenia, myositis, Sjogren's disease, bullous pemphigoid, and lupus nephritis.

A PEGylated cyclic-peptide inhibitor of complement component 3 (C3) built from two compstatin (Cp05) peptide domains bridged by a 40-kDa PEG chain; marketed as Empaveli/Aspaveli (subcutaneous, for paroxysmal nocturnal hemoglobinuria and, since July 2025, C3 glomerulopathy and primary IC-MPGN) and Syfovre (intravitreal, for geographic atrophy in age-related macular degeneration). It is one of the few complement-targeting therapeutic peptides to reach the market.

A self-administered, once-daily subcutaneous macrocyclic peptide that inhibits complement component 5 (C5), FDA- and EMA-approved for anti-AChR-positive generalized myasthenia gravis.

An FDA-approved RNA-interference (RNAi) therapy for hemophilia that works by lowering a natural blood-thinning protein rather than replacing a missing clotting factor. Fitusiran (brand name Qfitlia) is a GalNAc-conjugated small interfering RNA (siRNA) that is taken up by liver cells and silences the gene for antithrombin, the body's main brake on clotting. By reducing antithrombin, fitusiran 'rebalances' hemostasis so that people with hemophilia A or B can generate enough thrombin to form stable clots and bleed less often. It was approved by the U.S. FDA on March 28, 2025 - the first siRNA (RNAi) therapy for hemophilia and the first medicine that treats hemophilia by lowering antithrombin - for routine prophylaxis in adults and children aged 12 and older with hemophilia A or B, with or without factor VIII or IX inhibitors. A key practical advantage is that it is given as an infrequent subcutaneous injection (starting once every two months, as few as about six injections per year) and works regardless of hemophilia type or inhibitor status. In the pivotal Phase 3 ATLAS trials, fitusiran reduced the annualized bleeding rate by about 90% versus on-demand treatment. Because lowering antithrombin shifts the clotting balance, fitusiran carries a boxed warning for thrombotic (clotting) events and gallbladder disease, and it is now dosed to a target antithrombin level (15-35%) to reduce clot risk. Fitusiran is a prescription biologic administered under medical supervision - not a supplement or research chemical.

An FDA-approved RNA-targeted therapy that prevents hereditary angioedema (HAE) attacks by turning down production of a single blood protein rather than blocking it after it forms. Donidalorsen (brand name Dawnzera) is a GalNAc-conjugated antisense oligonucleotide (ASO) taken up by liver cells, where it binds the messenger RNA for prekallikrein (the gene KLKB1) and triggers its degradation, lowering circulating prekallikrein. Because prekallikrein sits at the top of the kallikrein-kinin cascade that generates bradykinin - the peptide that drives the swelling of HAE - reducing it prevents the runaway bradykinin surges responsible for painful, sometimes life-threatening attacks. It was approved by the U.S. FDA on August 21, 2025 as the first and only RNA-targeted prophylactic medicine for HAE, for routine prevention of attacks in adults and children aged 12 and older. It is given as an 80 mg subcutaneous self-injection by autoinjector once every four weeks, with the option to move to once every eight weeks in well-controlled patients. In the pivotal Phase 3 OASIS-HAE trial, donidalorsen reduced monthly HAE attacks by about 81% versus placebo over 24 weeks, and in the OASISplus switch study most patients who moved from other long-term prophylaxis preferred donidalorsen. Donidalorsen is a prescription biologic developed by Ionis Pharmaceuticals and administered under specialist care - not a supplement or research chemical.

Abelacimab (development code MAA868) is an investigational fully human monoclonal antibody being developed as a new kind of blood thinner (anticoagulant). It works by targeting Factor XI, a clotting protein that sits high in the coagulation 'cascade.' Abelacimab is described as a dual inhibitor: it binds the catalytic domain of Factor XI and locks the protein in its inactive (zymogen) shape, so it blocks both Factor XI itself and its activated form, Factor XIa, preventing the enzyme from being switched on by upstream triggers such as Factor XIIa or thrombin. The appeal of the Factor XI target is a long-standing observation in human biology: Factor XI contributes strongly to pathological clot formation (thrombosis) but only modestly to normal wound-sealing (hemostasis), so blocking it may prevent strokes and clots while causing much less bleeding than standard anticoagulants. Abelacimab is given as a once-monthly subcutaneous injection (with an intravenous loading option in some settings) and has a long duration of action. Its lead uses are stroke prevention in atrial fibrillation and the treatment and prevention of cancer-associated blood clots (venous thromboembolism, VTE). In the Phase 2b AZALEA-TIMI 71 trial, abelacimab reduced bleeding dramatically compared with the direct oral anticoagulant rivaroxaban - so much so that the study was stopped early - and it is now in Phase 3 development. Abelacimab was developed by Anthos Therapeutics, which Novartis originally helped launch and then reacquired in 2025. It is an investigational prescription biologic administered under medical supervision; it is not approved, and it is not a supplement, nootropic or research chemical.

Sebetralstat (brand name Ekterly) is a first-in-class, orally administered small-molecule inhibitor of plasma kallikrein and the first and only oral on-demand treatment approved for acute attacks of hereditary angioedema (HAE). HAE is a rare, sometimes life-threatening genetic disease in which unchecked activation of the plasma contact system floods the body with bradykinin, causing sudden, recurrent swelling of the skin, gut and airway. Plasma kallikrein is the enzyme that liberates bradykinin, so sebetralstat stops an attack by blocking kallikrein the moment symptoms begin - delivered as a tablet that can be taken at home rather than as an injection or infusion. The approved dose is 600 mg (two 300 mg tablets) at the earliest recognition of an attack, with a second 600 mg dose allowed at least 3 hours later if the response is inadequate or symptoms recur, up to a maximum of 1200 mg in 24 hours. Approval rests on the pivotal Phase 3 KONFIDENT trial (NCT05259917) - the largest HAE trial ever conducted, with 136 patients at 66 sites across 20 countries - a randomized, double-blind, placebo-controlled, event-driven crossover study in which sebetralstat cut the median time to the beginning of symptom relief to 1.61 hours (300 mg) and 1.79 hours (600 mg) versus 6.72 hours for placebo (p<0.0001 and p=0.0013), and also shortened the time to reduced attack severity and to complete resolution; results were published in the New England Journal of Medicine in 2024. The FDA approved Ekterly on July 7, 2025 for patients aged 12 and older, followed by European Commission and Swissmedic approvals on September 19, 2025 and UK MHRA approval. In 2026 the program widened further: an international pediatric HAE guideline named sebetralstat a first-line on-demand option for adolescents aged 12 and older, and in March 2026 KalVista reported positive interim Phase 3 results from the KONFIDENT-KID study in children aged 2 to 11 using an orally disintegrating tablet, with a US filing planned for late 2026. Developed by KalVista Pharmaceuticals, sebetralstat is a rescue (on-demand) therapy that complements the prophylactic HAE drugs garadacimab, donidalorsen, lanadelumab and berotralstat rather than replacing them.