TG Therapeutics Launches Post-Marketing Studies to Evaluate Briumvi in Pregnant and Breastfeeding MS Patients

Briumvi (ublituximab-xiiy) is an anti-CD20 monoclonal antibody FDA-approved to treat relapsing forms of multiple sclerosis (MS). The treatment is administered every six months as an hour-long intravenous infusion.

TG Therapeutics, Briumvi’s manufacturer, currently recommends that patients who can get pregnant use an effective method of contraception during treatment with Briumvi and for at least six months after the last Briumvi dose. A pregnancy test before each treatment is also recommended.

These precautions are based on data from animal studies suggesting Briumvi may cause harm to a developing fetus. There is insufficient data from human clinical trials of Briumvi to confirm this risk. It is also not known whether Briumvi passes into breast milk or the effect it could have on a breastfeeding infant.
To gather more data on the effect of Briumvi during pregnancy or lactation, TG Therapeutics is conducting two post-marketing studies on people with relapsing forms of MS who used Briumvi while pregnant or breastfeeding.

The study designs were presented by Riley Bove, M.D., from the Weill Institute of Neuroscience department of neurology at the University of California San Francisco, at the 2024 Consortium of Multiple Sclerosis Centers (CMSC) annual meeting, held May 29 through June 1, in Nashville, TN.

The studies were presented as separate posters titled “A Post-Marketing Study Evaluating the Presence and Concentration of BRIUMVI (ublituximab-xiiy) in Breastmilk (PROVIDE)” and “BRIUMVI Pregnancy Registry: A Prospective Study of Pregnancy and Infant Outcomes in Patients Treated with BRIUMVI (ublituximab-xiiy).”

The PROVIDE study is currently recruiting and plans to enroll 16 breastfeeding adults with relapsing forms of MS who independently chose to receive treatment with Briumvi while breastfeeding before study enrollment. Eligibility criteria included participants with infants born after at least 35 weeks of gestation and with a weight above the 10th percentile at birth and at the time of study enrollment.

The study’s primary objective is to determine the presence and concentration of Briumvi in the breast milk of lactating patients with relapsing forms of MS. Secondary objectives include estimates of the infants’ exposure to Briumvi and adverse events experienced by the infants.

Breast milk samples will be collected before the Briumvi infusion and 13 more times after the infusion over a period of 90 days.

The second study is not yet recruiting but plans to enroll 728 pregnant participants between the ages of 15 and 50 years. The study will include 364 participants with MS who used Briumvi during pregnancy and 364 who did not take Briumvi or any other anti-CD20 antibody during pregnancy.

The study’s primary objective is to compare the rate of major congenital malformations between participants exposed to Briumvi, those not exposed, and the general population. Secondary outcomes include minor congenital malformations, preterm birth, infant hospitalization, and pregnancy complications, such as pre-eclampsia, diabetes, miscarriage, or stillbirth.