How Janssen is offering hope for patients living with rare diseases

The pharmaceutical company’s ongoing commitment to autoantibody diseases is accelerating toward a potential treatment.

Hemolytic disease of the fetus and newborn (HDFN) is a potentially life-threatening disease, affecting up to 80 babies out of every 100,000 each year. The disease occurs when a pregnant person forms antibodies (called alloantibodies) that destroy the fetus’s red blood cells (hemolysis). The disease leads to various degrees of anemia, and in about one-quarter of cases, fetal death. It’s a rare pregnancy complication with no approved noninvasive management. 

“This disease has a devastating impact on the whole family,” says Dr. Katie Abouzahr, vice president and autoantibody portfolio development leader at Janssen Research & Development. “We need an approved, safe, and effective therapy for HDFN that is noninvasive.”

HDFN is one of the autoantibody-driven diseases that Janssen, Johnson & Johnson’s medical research and pharmaceutical company, is targeting in its decades-long work on addressing disorders of the immune system. A world leader in the immune-mediated disease space, Janssen’s portfolio already includes therapies for well-known autoimmune diseases, including rheumatoid arthritis, inflammatory bowel disease, psoriasis, and psoriatic arthritis. In recent years, Janssen’s work has expanded into a new type of immune-related condition. “We’re building on our portfolio into another form of immune-mediated disease, which is autoantibody-driven disease,” Abouzahr says.

Autoantibody diseases occur when antibodies—meant to attack viruses, bacteria, or other unwanted foreign invaders—turn against critical organs, tissues, and other vital parts of the body. This abnormal immune response is referred to as an autoantibody disease in the general population and as an alloantibody disease in cases of pregnancy when maternal antibodies attack the fetus. 

Worldwide, more than 200 million people are living with an autoantibody disease. But, as with HDFN, approved, targeted, safe, and effective therapeutic options are lacking—or nonexistent. Experts agree that clinical research is critical to advancing maternal-fetal health, yet only 1% of clinical trials include “pregnant” or “pregnancy” in the description.  

Janssen’s efforts to transform the lives of patients living with autoantibody diseases accelerated in 2020 when its parent company, Johnson & Johnson, acquired Momenta Pharmaceuticals. With this acquisition, Janssen is seeking to address unmet medical need in multiple autoantibody diseases across all three segments of autoantibody disease: maternal fetal, rare autoantibody, and prevalent rheumatology.

Abouzahr explains, “A pathway approach where you could potentially treat multiple diseases, rare or prevalent, with one mechanism is really exciting because you can bring a therapy to more patients, quicker and more efficiently.” 

“There’s also opportunity to explore therapies that are more targeted. We seek to address the problematic antibodies while allowing the rest of the immune function to be maintained,” Abouzahr says.

Janssen is conducting clinical trials in all three segments of autoantibody diseases, with 10 specific indications prioritized based on unmet need and actionable science. In the maternal fetal space, Janssen is conducting trials in HDFN; in the rare autoantibody segment, potential indications include myasthenia gravis, idiopathic inflammatory myopathies, and warm autoimmune hemolytic anemia; and finally, in the prevalent rheumatologic space, the diseases being studied include rheumatoid arthritis, systemic lupus erythematosus, and Sjögren’s syndrome.

The work isn’t without its challenges. For instance, it’s rare, and difficult, to conduct studies during pregnancy. “There are thousands of drugs in development at any one time, and very few are in pregnant patients, let alone in maternal-fetal medicine,” Abouzahr says. “On an individual level, thinking about these families and what they have to live through, we’d like to be able to change that dynamic for them.”

“Ultimately, we want to be able to have an approved, targeted, safe and effective therapy,” Abouzahr says. “We’re passionate and committed to finding one.”