Gallant Advances Canine Osteoarthritis IV-Delivered Stem Cell Therapy with Promising Pilot Data and Expanded FDA Conditional Approval Pathway Eligibility

Recent Milestones Aim to Bring a New Category of Care to One of Veterinary Medicine's Largest Unmet Needs

• Gallant granted eligibility for expanded conditional approval by FDA-CVM for canine osteoarthritis (OA) stem cell therapy; targeting conditional approval in 2028.
• Randomized, blinded, placebo-controlled pilot study shows statistically significant improvement in Gallant's uterine-derived mesenchymal stromal cell (UMSC) treated dogs for validated pet parent outcomes.
• No treatment-related serious adverse events observed; early data supports the safety of repeated dosing with donor-derived UMSCs

SAN DIEGO, May 6, 2026 /PRNewswire/ -- Gallant, an animal health biotechnology company pioneering off-the-shelf mesenchymal stromal cell (MSC) therapies for pets, today announced that its canine osteoarthritis (OA) MSC therapy program has been granted eligibility to use the U.S. Food and Drug Administration Center for Veterinary Medicine's (FDA-CVM) expanded conditional approval pathway. The company also announced positive results from a randomized, placebo-controlled pilot study evaluating intravenous (IV) UMSCs in client-owned dogs with naturally occurring OA.

The announcement comes as the veterinary community marks Arthritis Awareness Month. OA is a common and often underdiagnosed condition, affecting more than 20% of dogs over one year of age, 40% of dogs four years of age, and up to 80% of dogs over eight years of age. Despite its prevalence, the disease is frequently misunderstood as a wear-and-tear disease associated with age-related joint degeneration, which has real consequences for how and when dogs receive care.

Research has established that pro-inflammatory processes driven by both local and systemic immune activity play a central role in the onset and progression of OA. The disease commonly affects young dogs, and cartilage degeneration, once underway, is progressive. MSC therapy, which works by modulating these immune pathways, targets the root cause of disease.

The study enrolled 88 client-owned dogs with radiographically confirmed OA and observable lameness or pain in at least one affected peripheral joint. Dogs were randomly assigned to receive two intravenous injections, administered 14 days apart, of either UMSCs or a saline placebo. Dogs were assessed by pet parents and veterinarians through Day 90, which served as the primary efficacy endpoint.

Dogs receiving UMSCs demonstrated significant improvement compared to placebo in validated pet parent-reported outcome measures at Day 60 and 90. Pet parent and veterinarian assessments of mobility, quality of life and pain consistently favored the UMSC–treated group.

No treatment-related serious adverse events were observed, and these early findings support the safety of repeat IV dosing with donor-derived UMSCs.

"In this pilot study, we're pleased to see that repeat IV dosing was well tolerated, with positive signals across key outcomes in dogs with osteoarthritis," said Dr. Rebecca Windsor, DVM, DACVIM, vice president of Veterinary Affairs at Gallant. "By targeting the systemic and local immune dysregulation that precedes the progressive, degenerative changes of OA, MSC therapy has the potential to not only control clinical signs but also impact the course of disease."

A key feature of Gallant's approach is the IV delivery route. Historically, cell therapy for OA has meant injection directly into the joint (or often multiple joints) - a procedure that requires sedation or anesthesia, specialized training and often referral to a specialist. Gallant's ready-to-use, off-the-shelf therapy is designed for simple IV administration, so it's easily accessible to all veterinarians, for any dog that needs it, in any practice setting.

The FDA granted Gallant expanded conditional approval eligibility for both its canine and feline OA programs, a regulatory designation expected to bring these therapies to market earlier, meeting a well-established unmet medical need with potential conditional approval targeted for 2028.

"This is another positive step toward revolutionizing how we treat OA in dogs," said Dr. Linda Black, DVM, Ph.D., CEO of Gallant. "We're encouraged by the pilot data, and it moves us closer to making regenerative medicine a real and practical option for all veterinarians treating dogs suffering from OA."

Gallant's free, RACE-approved continuing education platform, GallantU, provides veterinary professionals with practical education on regenerative medicine, including modules dedicated to canine OA. Sign up at learn.gallant.com and join the free upcoming webinar titled Canine Osteoarthritis: Current Concepts and Advancement in Management on May 13, 2026, at 7:00 p.m. EDT. 

For information on Gallant's Canine OA pilot study data, go to: https://bit.ly/4eR82Z0

About Gallant
Gallant is an animal health biotechnology company creating a new category of veterinary care with a pipeline of off-the-shelf, ready-to-use stromal cell therapies targeting the root cause of disease in pets. Led by pioneers in veterinary regenerative medicine with deep expertise in development, manufacturing, and commercialization, Gallant is making regenerative medicine accessible — moving beyond symptom management to restoring health at the source. Learn more at www.gallant.com.

Gallant's uterine-derived mesenchymal stromal cell therapy for canine osteoarthritis is an investigational new animal drug and has not received FDA approval or conditional approval. Availability is pending regulatory review.

Media Contact:
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SOURCE Gallant