FDA approves two gene therapies for sickle cell disease, including first that uses CRISPR/Cas9

These approvals represent an important medical advance with the use of innovative cell-based gene therapies to target potentially devastating diseases and improve public health,

Today’s actions follow rigorous evaluations of the scientific and clinical data needed to support approval, reflecting the FDA’s commitment to facilitating the development of safe and effective treatments for conditions with severe impacts on human health.

Peter Marks, director of the FDA’s Center for Biologics Evaluation and Research. 

The Approval of Two Therapies

In a landmark moment for genetic medicine and sickle cell disease patients, the FDA on Friday approved not just one but two gene therapies for the disease: Vertex Pharmaceuticals’ and CRISPR Therapeutics’ Casgevy, marking the first-ever approval of a CRISPR-based medicine in the US, and Lyfgenia, Bluebird Bio’s lentiviral gene therapy.

Sickle cell disease is a group of inherited blood disorders affecting approximately 100,000 people in the US. It is most common in African Americans and, while less prevalent, also affects Hispanic Americans. 

The primary problem in sickle cell disease is a genetic mutation that causes the red blood cells to develop a crescent or “sickle” shape. These sickled red blood cells restrict the flow in blood vessels and limit oxygen delivery to the body’s tissues, leading to severe pain and organ damage. The recurrence of these problems can lead to life-threatening disabilities and possibly early death. 

This is the very first time that some patients have ever imagined that they might not have to live their entire lifespan with the consequences of sickle cell disease,

Alexis Thompson, the chief of the division of hematology at Children’s Hospital of Philadelphia and investigator on the clinical trials that led to the therapies’ approvals.

The Extreme Price Tags

The treatments are approved for sickle cell disease patients 12 years of age and older who experience painful attacks associated with the disease. Vertex will charge $2.2 million in the US for Casgevy, while Bluebird will charge $3.1 million for Lyfgenia. While the approval of these life-changing therapies is very exciting, the expensive treatments are going to be out of reach for many. 

Contributing to the high costs is the long and complex administration overhead associated with these therapies. Patients’ blood stem cells are first removed and shipped away to a manufacturing site to be engineered. The patients often have to stay in the hospital for weeks and receive chemotherapy to clear space for the new stem cells, which are then infused back after they are engineered.

When a patient undergoes treatment with Casgevy, their blood stem cells are edited to express fetal hemoglobin — a form of the oxygen-carrying protein that is active during fetal development but turned off and replaced by adult hemoglobin after birth. 

With Lyfgenia, viral vectors are used to deliver a functional beta-globin gene to the patient’s blood stem cells. However, viral-vector manufacturing has not been scaled to meet the demand for all the newly approved gene therapies. A shortage of viral vectors, caused by the manufacturing challenges, also contributes to the extreme costs of the medicine. 

Making healthcare accessible to all

I think it’d be a shame if we finally come up with a therapy and there’s no access for patients

We’re doing everything we can to make sure people, not just the payers, but the entire ecosystem, understands that aspect.

CRISPR Therapeutics CEO Sam Kulkarni said ahead of the approval.

As we celebrate the approval of the two therapies, their high costs are a stark reminder that global access to healthcare remains a challenge. 

At Good AI, our mission is to invest in companies that can change the landscape by integrating the latest advances in AI, Synthetic Biology, Genetic Editing, Digital Health, and Precision Medicine. 

For example, Mekonos is developing a System-On-a-Chip ( SoC ) platform that will enable molecular delivery in gene editing and synthetic biology. Blending innovations from MEMS (micro-electromechanical system), Microfluidics, and Surface Chemistry, Mekonos is committed to removing the persisting hurdles surrounding the production of cell and gene therapies so we can rapidly move into new disease areas, reaching targets once deemed undruggable and one-day putting cell and gene therapies into the hands of more people.

Focusing on 1) improving supply chain efficiency, 2) streamlining clinical trials, 3) speeding up drug discovery and 4) incentivizing both payors and providers to deliver value-based outcomes, our portfolios are working tirelessly to make healthcare accessible to all.