The ground-breaking allure of CRISPR science attracted billions to biotech companies since the technology emerged a dozen years ago. This December, the first CRISPR treatment may reach the commercial marketplace when the FDA determines the fate of Vertex Pharmaceuticals’ (VRTX) and CRISPR Therapeutics (CRSP) learn the fate of exa-cel as an enduring therapy for sickle cell disease.
As exciting as exa-cel appears to sickle cell families, questions still remain on how effective the drug can be and how many will be able to receive exa-cel if it is approved.
In sickle cell disease, sickled red blood cells block blood flow causing certain tissues to become deprived of oxygen. The block of blood flow sets in motion vaso-oclusive crises (VOCs) and a subsequent inflammatory response as the body attempts to rectify the problem. VOCs often need to be treated at a hospital with intravenous hydration and analgesics. VOC treatments can be chronic for sickle cell patients, costing between $4 million and $6 million over a lifetime, according to Vertex.
Exa-cel steps into this arena, potentially promising it can reduce or eliminate painful and debilitating VOCs for severe sickle cell patients for their lifetimes. Why? The perceived scientific power of CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats). CRISPR is molecular research tool with the demonstrated ability to alter DNA to correct genetic defects and consequently modify DNA sequences. Cells from patients are extracted first, then altered. The re-engineered cells (e.g., exa-cel) are then infused in the patient to correct and modify, permanently, the aberrant genetic defects and DNA sequences.
The durability of exa-cel will be evaluated initially by an FDA advisory committee. Should the committee vote for approval, the FDA staff also needs to sign off but the agency typically does not turn back an affirmative vote by the committee. The decision process involving what price the drug manufacturer will charge is less clear.
This week, Vertex said it would be flexible in setting a price for exa-cel. Vertex hypothetically could argue exa-cel deserves to be priced slightly less than $4 million because it is a one-time treatment. Sickle cell disease afflicts about 100,000 people in the US, primarily in the African American community. About two-thirds of sickle cell patients have government health insurance, either in Medicaid, Medicare or VA programs. The majority of the sickle cell patients are enrolled in Medicaid. Accordingly, Vertex said it is focusing its potential launch and pricing decision in the 24 states with the highest sickle cell prevalence.
But what will the price be and can exa-cel effectively reach the patients who need the therapy? The answers usually are determined after a drug is approved. Analysts following Vertex believe the company’s pricing “flexibility” may end up at a price of $2 million per treatment, far less than the current, estimated $4 million cost in sickle cell disease. And less than the record $3.5 million cost for a one-time treatment set by CSL Limited’s (OtherOTC:CSLLY) hemophilia B gene therapy Hemgenix.
Vertex is not bound to a $2 million price for exa-cel, nor is it obligated to be sure the drug reaches the majority of sickle cell patients who would benefit. Should state Medicaid agencies not have the funds available for exa-cel treatment, Vertex and certain states are unlikely to reach an agreement on introducing the drug in the specific state.
An FDA advisory committee to review exa-cel probably will convene in November and approval could follow one month later. Once exa-cel clears those two hurdles, sickle cell families will learn more about access and costs. More than likely, a few will be disappointed.