Early Hemlibra use prevents bleeding in babies with hem A
Real-world study finds treatment safe, effective
Starting Hemlibra (emicizumab) early is safe and helps to prevent bleeding in babies with severe hemophilia A who are untreated or minimally treated, though doctors should still monitor for self-reactive antibodies that can make other treatments less effective, a study suggested.
The study, “Emicizumab in Previously Untreated Patients and Minimally Treated Patients With Hemophilia A: A Comparative Study Between Two International Cohorts,” was published in Pediatric Blood & Cancer.
Hemophilia A is caused by deficiency in a protein called factor VIII (FVIII), due to mutations in the F8 gene. This prevents the blood from clotting properly and subsequently leads to excessive bleeding. Treatment typically involves replacing the missing FVIII protein. However, the body may sometimes react by developing self-reactive antibodies (inhibitors). This problem is more common in patients receiving treatment for the first time.
Hemlibra, approved for use in children and adults with hemophilia A with or without inhibitors, mimics the function of FVIII, helping the blood clot and reducing the frequency of bleeds. Unlike other treatments injected into the bloodstream, Hemlibra is injected under the skin, making it more comfortable, especially for younger children.
Bleeding rate slows with treatment
The study examined the safety and effectiveness of Hemlibra in real-world settings. One center included 22 babies with severe hemophilia A who had received a median of 3.5 days of FVIII replacement therapy before starting Hemlibra at a median age of 5 months. The other center included 19 previously untreated babies who started Hemlibra at a median age of 8 months.
After starting Hemlibra, minimally treated babies were followed for a median of 27 months, and previously untreated babies for a median of 29 months.
The median annualized bleeding rate — the number of bleeds adjusted to one year — was 0.1 for minimally treated babies and zero for previously untreated babies. Previously untreated babies experienced five times fewer bleeds than minimally treated babies.
The time to the first bleeding event was significantly longer in previously untreated infants. In fact, none of the babies in this group experienced a bleeding episode during the observation period. In contrast, minimally treated infants had their first bleed at a median age of 13 months. A higher proportion of previously untreated babies had zero bleeds during follow-up (85% vs. 50%).
Four minimally treated babies developed inhibitors against FVIII. They all had high-risk genetic mutations, and two had experienced major bleeds before the inhibitors appeared. No previously untreated babies developed inhibitors. With Hemlibra, there was a reduction of these inhibitors, likely because the babies were less exposed to FVIII.
While there were age differences and cultural practices between the two groups of babies, the results suggest “early emicizumab prophylaxis in infants with severe hemophilia A is safe, well-tolerated, and effective at reducing bleeding episodes,” the researchers concluded.
About the Author
