Trellis Bioscience has raised $9 million in Series C funding to support the clinical development of calpurbatug, also known as TRL1068. The investigational monoclonal antibody is being evaluated as a treatment for chronic prosthetic joint infections.
Existing investors New Science Ventures and Easton Capital participated in the financing. New investors included AMR Action Fund, The Doctor Group and orthopedic surgeons with expertise in prosthetic joint infections.
The round brings Trellis Bioscience’s total equity funding to approximately $35 million. The company has also received a similar amount of non-dilutive grant support from the National Institute of Allergy and Infectious Diseases and CARB-X.
Junjun Gao, a principal at AMR Action Fund, has joined Trellis Bioscience’s board of directors in connection with the investment. The appointment adds antimicrobial investment and industry experience to the company’s leadership.
Trellis plans to use the financing to complete its Phase 2 clinical trial of calpurbatug in patients with prosthetic joint infections. The fully enrolled study is evaluating the therapy as part of a debridement, antibiotics and implant retention procedure known as DAIR.
Prosthetic joint infections can develop after knee or hip replacement procedures and are often difficult to eliminate. Trellis estimates that the condition affects more than 25,000 patients annually in the United States, representing approximately 1% to 2% of joint replacement recipients.
There are currently no approved drug therapies specifically for prosthetic joint infections. The standard treatment frequently involves a two-stage surgical revision in which the infected implant is removed and replaced during separate procedures.
Trellis said the approach can be physically demanding and is associated with reduced quality of life, treatment failures and elevated five-year mortality. The cost of managing a prosthetic joint infection can exceed $400,000 per patient.
DAIR offers a less invasive alternative by cleaning infected tissue, administering antibiotics and retaining the existing implant. However, the procedure has a higher failure rate in chronic infections, particularly when bacteria are protected by a biofilm.
Biofilms are structured communities of bacteria surrounded by a protective matrix that can form on implanted medical devices. This barrier can make the bacteria substantially more difficult for antibiotics and the immune system to reach and eliminate.
Calpurbatug is designed to disassemble the biofilm and expose the underlying bacteria to antibiotic treatment. Trellis believes this mechanism could establish a new therapeutic category for drug-resistant infections involving implanted devices.
The company said preclinical data and early clinical findings indicate that calpurbatug can disrupt biofilms associated with prosthetic joint infections. The treatment is intended to improve the effectiveness of DAIR while reducing the need for more extensive revision surgery.
Trellis previously completed a first-in-human study of calpurbatug under an investigational new drug application cleared by the U.S. Food and Drug Administration. The Phase 1 trial evaluated safety and pharmacokinetics and provided early evidence of biofilm-disrupting activity.
The ongoing Phase 2 trial is testing TRL1068 in combination with the DAIR procedure. Trellis expects to report topline results from the study in the second quarter of 2027.
The FDA has granted calpurbatug Orphan Drug, Fast Track and Qualified Infectious Disease Product designations. These programs may support a more efficient development and review process, while the QIDP designation could provide additional market exclusivity following a potential approval.
Trellis developed a proprietary platform for cloning native human antibodies from white blood cells. The company applies the technology to infectious diseases by identifying antibodies from patients who have recovered from the targeted condition.
In addition to its biofilm program, Trellis is developing antiviral antibodies addressing unmet medical needs. One of those candidates is currently being evaluated in a clinical trial.
KEY QUOTES:
“We’re excited to have the backing of AMRAF, the most prominent investor in the antimicrobial space, as we move ahead in our efforts to redefine how antibiotic-resistant infections are treated in the future. By disrupting bacterial biofilm, calpurbatug represents a new class of agents with potential utility in a substantial number of antibiotic-resistant infections.”
Geoff Dillon, CEO of Trellis Bioscience
“The emerging results from clinical trials for augmenting the DAIR procedure with TRL1068 suggest that this innovative drug will yield outcomes superior to two-stage revision in a range of bacterial infections. That would be a true game changer in the field, better results and less grueling for the patient.”
Jason Adams of The Doctor Group
“The PJI treatment challenge and financial burden are expanding as more joint replacement surgeries are expected for the aging U.S. population.”
John Friedman, Chairman of Easton Capital
“Infection is a risk with any surgical procedure, and prosthetic joint infections can be devastating for patients. The growing threat of antimicrobial resistance is making these infections increasingly difficult to treat. We are pleased to support the Trellis team as they work to develop a therapy that could improve outcomes for patients and help preserve the antibiotic safety net that underpins modern surgical care.”
Henry Skinner, CEO of AMR Action Fund
