First‑in‑class drugs are therapies with entirely new approaches that improve patient outcomes and fundamentally change treatment paradigms.This week, PharmaCompass brings a compilation of 2025’s most promising first-in-class drug candidates. With their US Food and Drug Administration (FDA) action dates in 2025, many of these drugs, once approved, hold the potential of becoming blockbusters.Ionis’ donidalorsen, Sanofi’s fitusiran, Cytokinetics’ aficamten poised to transform patient careIonis’ donidalorsen is an exciting candidate designed to tackle hereditary angioedema (HAE), a rare condition marked by unpredictable and potentially life‑threatening swelling episodes.This novel antisense oligonucleotide works by “silencing” the messenger RNA that codes for prekallikrein — a protein that triggers inflammation leading to swelling. Instead of blocking a protein once it’s made, donidalorsen stops the cell from producing it in the first place. This precision approach could mean fewer infusions and reduced side effects compared to traditional treatments.Another promising candidate is Sanofi and Alnylam Pharmaceuticals’ fitusiran. It employs the technology of small interfering RNA (siRNA) to lower levels of antithrombin — a natural protein that, when in excess, can impair the blood’s ability to clot. By reducing antithrombin, fitusiran rebalances the blood’s clotting process in patients with hemophilia A and B.Similarly, Cytokinetics’ aficamten is designed to treat
obstructive hypertrophic cardiomyopathy (oHCM), a condition in which the heart
muscle becomes abnormally thick, obstructing blood flow. Aficamten works by inhibiting cardiac
myosin, a protein that drives heart muscle contraction. This helps relieve
symptoms like shortness of breath and chest pain. If approved, aficamten is
expected to rake in annual sales of US$ 2.8 billion by 2030.UroGen, J&J’s candidates eye US$ 5 bn markets; AbbVie, Summit’s meds target lung cancerUroGen Pharma’s UGN‑102 is poised to redefine the treatment of non‑muscle‑invasive bladder cancer. This innovative formulation uses a reverse thermal gel technology that transforms from a liquid into a gel once inside the bladder. This change ensures that the chemotherapeutic agent, mitomycin, remains in contact with the bladder lining for a longer period, increasing its effectiveness at eradicating cancer cells and reducing the risk of recurrence.For patients, UGN‑102 could mean a non‑surgical, outpatient treatment option that is less invasive than traditional surgical methods. If approved, UGN-102 could address a US market of approximately 82,000 patients annually, translating into a market opportunity exceeding US$ 5 billion, according to company estimates.Johnson & Johnson’s nipocalimab is a new treatment aimed at helping people with autoimmune diseases — a group of conditions where the body’s defense system mistakenly attacks its own healthy cells. Nipocalimab works by blocking the neonatal Fc receptor (FcRn), thereby lowering the levels of pathogenic antibodies that drive many autoimmune disorders. J&J had acquired this FcRn blocker in 2020 as part of its US$ 6.5 billion takeover of Momenta Pharmaceuticals. J&J is trialing the drug in as many as 10 indications and expects peak annual sales in excess of US$ 5 billion.AbbVie’s antibody-drug conjugate (ADC), telisotuzumab vedotin, is designed as a “guided-missile” to deliver toxic drugs directly to cancer cells while sparing healthy tissues. Telisotuzumab vedotin targets c‑Met, a receptor that is over-expressed in certain cancers such as non‑small cell lung cancer (NSCLC). There are currently no approved anti-cancer therapies specifically for c-Met over-expressing NSCLC.Summit Therapeutics’ ivonescimab is a cutting‑edge bispecific antibody designed specifically for NSCLC. Unlike traditional therapies that target a single molecule, ivonescimab binds simultaneously to a tumor-specific antigen on cancer cells and to a receptor on T cells, effectively bringing these two together so the body’s own immune system can recognize and attack the tumor. This dual engagement strategy helps overcome common mechanism tumors.Insmed’s Brensocatib is an innovative, first‐in‐class oral inhibitor of dipeptidyl peptidase‑1 (DPP‑1) that targets a key step in the inflammatory cascade. DPP‑1 is responsible for activating neutrophil serine proteases — enzymes that, when overactive, can cause significant lung tissue damage in
conditions such as non‑cystic fibrosis bronchiectasis. Brensocatib is expected to clock annual sales of US$ 2.8 billion by 2030.Gepotidacin, an investigational antibiotic developed by GSK, is poised to make a
significant impact in the treatment of uncomplicated urinary tract infections
(uUTIs) and urogenital gonorrhea. If approved, it would be the first oral
antibiotic in a new class for uUTIs in over two decades.Arrowhead, Regenxbio,
Ultragenyx address rare, genetic diseasesArrowhead Pharmaceuticals is developing an innovative gene-targeting therapy — plozasiran. This drug uses RNA interference (RNAi) to interrupt the gene responsible for producing apolipoprotein C‑III (APOC3), a protein that regulates blood triglyceride levels. For people with severe hypertriglyceridemia or familial chylomicronemia syndrome (FCS) — a severe and rare genetic disease for which there are currently no FDA‑approved treatments — high triglyceride levels can lead to pancreatitis and other serious cardiovascular issues. Regenxbio’s RGX‑121 is a one‑time gene therapy candidate for
Hunter syndrome (MPS 2), a rare, inherited disorder that causes progressive neurological decline. The therapy uses a harmless virus to deliver a functional copy of the gene encoding iduronate‑2‑sulfatase (I2S) directly into the central nervous system. By restoring the missing enzyme, RGX‑121 aims to slow or even reverse the harmful buildup of substances in the brain that drive the disease’s progression.Another promising candidate is Ultragenyx Pharmaceuticals’ one-time intravenous gene therapy UX111 for Sanfilippo syndrome type A (MPS 3A). This devastating disorder, which leads to severe
neurodegeneration in children, currently has no effective treatment. UX111 uses an adeno‑associated virus (AAV) to deliver a working copy of the SGSH gene, the deficiency of which is responsible for the disease. By enabling the body to produce the missing enzyme, UX111 holds the promise of slowing or even halting the progression of neurodegeneration.Our viewThis year has already seen several first-in-class approvals, such as Vertex’s suzetrigine (Journavx), a pioneering non‐opioid analgesic redefining pain management; SpringWorks’ mirdametinib (Gomekli), a breakthrough MEK inhibitor for a genetic disorder that often leads to the growth of benign tumors along nerves and; AstraZeneca and Daiichi’s ADC datopotamab deruxtecan (Datroway).Despite the volatile political environment in the US and its
impact on federal agencies like the FDA, we are hopeful that many of the
first-in-class drugs mentioned in this article will make a debut in 2025.