Bimagrumab

After quickly enrolling its pivotal trial and recruiting more patients with a rare muscle disease than anticipated, Abcuro went to its board to explore a $60 million to $80 million fundraise. That initial ask in May turned into a $200 million Series C, CEO Alex Martin told Endpoints News , and the fresh funding is expected to help the company prepare to commercialize its monoclonal antibody, dubbed ulviprubart, or ABC008. The Newton, MA-based biotech announced the financing on Thursday morning. New Enterprise Associates led the round, while Foresite Capital also joined the investor syndicate alongside existing backers Bain Capital Life Sciences and RA Capital — and at least 10 other investors, including Sanofi’s venture arm. Abcuro expects to have data from a Phase 2/3 trial in inclusion body myositis (IBM) in the first half of 2026 and then file for approval in the US and Europe, Martin said. The company enrolled 272 patients against an original target of 231 participants for the 76-week trial. There are no FDA-approved medicines for the rare autoimmune disease mainly found in those 50 years and older. It leads to progressive muscle weakness and can thwart the ability to walk, swallow and perform other daily functions. The biotech’s drug targets killer cell lectin-like receptor G1, or KLRG1. By hampering cytotoxic T cells, and sparing regulatory and memory T cells, Abcuro thinks it can tamp down inflammation and help muscles “regenerate and decrease the chronic pathogenesis of the disease,” chief medical officer Jeff Wilkins told Endpoints in 2023 when the company announced a $155 million Series B . Wilkins noted that other treatments, including methotrexate and rituximab, have failed in IBM. Novartis tested an antibody as a treatment for IBM, but the investigational medicine was repurposed by another company for obesity after it failed in IBM. Eli Lilly now owns the asset, named bimagrumab. Orphazyme, which is now owned by Zevra, also tried arimoclomol as a treatment for IBM. The drug was approved last year for a different progressive disease, called Niemann-Pick disease type C. “We noticed that they had screen failed about 12% of patients” in the arimoclomol trial, Martin said. “We ended up screen failing almost twice the rate of that because we wanted to make sure we had a patient population we thought would be best suitable for this trial.” Abcuro has received offers for both acquisitions and partnerships from mid- and large-sized companies, according to Martin. Instead, the company is looking for a chief commercial officer and “beginning to look at the broader picture at the commercial team,” Martin said. It currently employs about 40 people. “Right now, we’re very comfortable with the plan that we have to take this drug through registration,” he said. Abcuro also plans to take early-stage clinical data in patients with T cell large granular lymphocytic leukemia to the FDA in the “coming quarter or two” to see about a Phase 2/3 program for ulviprubart, according to Martin. It’s also considering moving into other indications like multiple sclerosis or Sjögren’s disease, the CEO said. “We’re going to learn a lot from the IBM trial,” Martin said. It’ll help inform whether Abcuro wants to “stick in the neurology area or we want to venture further afield. There’s implications in type 1 diabetes, lupus and other autoimmune diseases, so we’ll see what we see in the IBM trial and then make a decision.”

The Series C funding round was led by New Enterprise Associated (NEA). Credit: sesame via Getty Images. US-based biotech Abcuro has raised $200m to advance the development of its monoclonal antibody ulviprubart in the rare muscle disease called inclusion body myositis (IBM). The funding round, led by New Enterprise Associates (NEA), will be used to complete the Phase II/III MUSCLE clinical trial (NCT05721573) of ulviprubart. Assuming positive results from the study, Abcuro said it plans to file a biologics licence application (BLA) and will use some of the funds to support the expansion of manufacturing capabilities and “other pre-commercial activities this year”. Abcuro completed patient enrolment in the MUSCLE trial in June 2024, and topline data is expected in H1 2026, said Abcuro’s chief medical officer H. Jeffery Wilkins in a previous announcement. The MUSCLE study compares two dose levels of ulviprubart with placebo at 76 weeks in subjects with IBM, followed by a four-week safety follow-up period. IBM is a group of autoimmune diseases that involve inflammation of the muscles or associated tissues. The inflammation causes muscle weakness that may worsen over time, leading to difficulty in swallowing and weak wrists or fingers. There are currently no US Food and Drug Administration (FDA)-approved treatments specifically for IBM. Patients are generally managed using physical therapy, occupational therapy, speech therapy, and exercise. Despite being an autoimmune disorder, the disease is generally unresponsive to corticosteroids and immunosuppressive drugs. The IBM research space is sparse, with companies like Novartis facing hurdles in developing effective treatments. Novartis tested investigational antibody bimagrumab in the Phase IIb/III RESILIENT trial (NCT01925209), but the drug failed to show functional benefits in subjects with IBM. This led to the programme’s termination in 2016. Novartis later licensed bimagrumab to Versanis Bio – the subject of a $1.9bn Eli Lilly acquisition in July 2023. Abcuro’s candidate works by targeting killer cell lectin like receptor G1 (KLRG1). The goal is to deplete the highly toxic T cells that chronically attack the muscle tissue in patients with IBM. Abcuro is also testing ulviprubart in a Phase I/II study (NCT05532722) in T cell-large granular lymphocytic leukaemia (T-LGLL), a blood cancer that occurs when certain T cells and natural killer cells mutate. This latest funding builds on the $155m Abcuro raised in a Series B round co-led by Redmile Group and Bain Capital Life Sciences in August 2023. The company outlined then that it anticipates a regulatory approval filing in 2026.