Advances in Hemophilia Treatment

There are positive developments in treatment for Hemophilia and the introduction of new gene therapies. As background, the CDC defines Hemophilia as an inherited bleeding disorder in which the blood does not clot properly. This can lead to spontaneous bleeding as well as bleeding following injuries or surgery. Blood contains many proteins called clotting factors that can help to stop bleeding.

People with Hemophilia have low levels of either factor VIII or factor IX. The severity of Hemophilia that a person has is determined by the amount of factor in the blood. The lower the amount of the factor, the more likely it is that bleeding will occur which can lead to serious health problems.

Hemophilia occurs in about 1 of every 5,000 male births, and about 20,000-33,000 males in the United States are living with the disorder, affecting people from all racial and ethnic groups. The CDC explains that there are several different types of hemophilia and the following two are the most common:

• Hemophilia A (Classic Hemophilia) This type is caused by a lack or decrease of clotting factor VIII.

• Hemophilia B (Christmas Disease) This type is caused by a lack or decrease of clotting factor IX.

Hemophilia A is about four times as common as Hemophilia B, and about half of those affected have the severe form.

While a person can develop Hemophilia later in life, the majority of cases involve middle-aged or elderly people, or young women who have recently given birth or are in the later stages of pregnancy.

Currently, Hemophilia medications are extraordinarily expensive. The cost of drug therapy for a person with hemophilia can be several hundred thousand dollars per year and annual treatment costs of $1 million or more are not uncommon for patients with the most severe forms of the disease.

New Gene Therapies Relieve High Patient Burden of Disease

Late last year, the U.S. Food and Drug Administration approved Hemgenix (etranacogene dezaparvovec) developed by CSL Behring LLC, an adeno-associated virus vector-based gene therapy for the treatment of adults with Hemophilia B (congenital Factor IX deficiency) who currently use Factor IX prophylaxis therapy, or have current or historical life-threatening hemorrhage, or have repeated, serious spontaneous bleeding episodes.

Most individuals who have Hemophilia B and experience symptoms are men, with its prevalence in the male population about one in 40,000. Many women carriers of the disease have no symptoms. However, an estimated 10-25% of women carriers have mild symptoms, although in rare cases, women may have moderate or severe symptoms. 

Hemgenix is a one-time gene therapy product given as a single dose by IV infusion. Hemgenix consists of a viral vector carrying a gene for clotting Factor IX. The gene is expressed in the liver to produce Factor IX protein, to increase blood levels of Factor IX and thereby limit bleeding episodes. 

Unleashing Hope: Empowering Lives

Marstacimab is in development as a prophylactic treatment to prevent or reduce the frequency of bleeding episodes in individuals with severe Hemophilia A or moderately severe to severe Hemophilia B with or without inhibitors. In mid-June 2023, Pfizer revealed advances in the development of marstacimab. The Phase 3 BASIS clinical trial evaluating marstacimab concluded that its primary endpoints were met, having demonstrated statistically significant and clinically meaningful effects.

Clinical Study Details

During the trial, Pfizer assessed the efficacy of marstacimab in 116 patients diagnosed with Hemophilia A or B. Individuals without inhibitors to factor VIII or factor IX received standard care for six months, followed by a switch to marstacimab for an additional 12 months.

Clinical Outcomes

The findings demonstrated that among those who previously required on-demand factor replacement intravenous therapy, the switch to marstacimab resulted in a 92% reduction in bleeding incidents. The authors concluded that marstacimab demonstrated improvement through a 35% reduction in annualized bleeding rate as compared to the prophylactic treatments.

The inhibitor cohort of the BASIS trial is completing enrollment and is expected to read out as early as late 2024, providing hope to individuals living with Hemophilia A and B for improved patient outcomes in the near future.

Pfizer also currently has two additional Phase 3 programs investigating novel treatment options for people living with Hemophilia, fidanacogene elaparvovec and giroctocogene fitelparvovec, investigational gene therapy treatments being studied for the treatment of adults living with Hemophilia A and Hemophilia B, respectively.

September Highlights AscellaHealth Gene Therapy and Specialty Pharmacy Awareness Month

As we find ourselves in the heart of September's AscellaHealth Gene Therapy and Specialty Pharmacy Awareness Month, the progress in rare and orphan diseases continues to inspire us.

At AscellaHealth, our unwavering commitment to education and providing industry-focused information empowers all stakeholders to navigate the evolving landscape of gene therapies and specialty medications. With over 900 ongoing gene therapy breakthroughs and specialty drugs accounting for nearly 60% of pharmacy benefits costs, staying informed and up-to-date on all industry developments remains vital in driving improved clinical health outcomes and quality of life for patients with complex, rare diseases.

As we unite in celebrating Gene Therapy and Specialty Pharmacy Awareness Month, we stand unified in our quest to enhance access to life-changing treatments and to foster better health outcomes and quality of life for communities across the nation. Together, let's unleash hope and empower lives through the power of knowledge and awareness.