NEW YORK – The Institute for Clinical and Economic Review (ICER) on Thursday said two gene therapies currently under review at the US Food and Drug Administration to treat sickle cell disease could be reasonably priced as high as $2.05 million.
ICER, a nonprofit that conducts independent value assessments of healthcare interventions, said current evidence suggests Bluebird Bio's lovotibeglogene autotemcel (lovo-cel) and Vertex Pharmaceuticals and CRISPR Therapeutics' exagamglogene autotemcel (exa-cel) could be cost-effective if priced between $1.35 million and $2.05 million.
Lovo-cel uses a lentivirus vector to deliver functional copies of a modified HBB gene designed to produce anti-sickling hemoglobin into patients' own hematopoietic stem cells ex vivo. Exa-cel uses CRISPR-Cas9 to edit patients' hematopoietic stem and progenitor cells ex vivo to alter the BCL11A gene in an effort to reactivate high levels of fetal hemoglobin in red blood cells. The adult form of the oxygen-carrying protein hemoglobin is lacking or dysfunctional in patients with sickle cell disease.
The FDA is expected to issue a decision on whether to approve lovo-cel by Dec. 20 and exa-cel by Dec. 8.
Both lovo-cel and exa-cel have demonstrated that they can "dramatically" reduce the frequency of painful vaso-occlusive crises in patients with severe sickle cell disease, ICER said. However, there is still uncertainty around the long-term efficacy and safety of the gene therapies. That's particularly true for exa-cel, which could be the first approved CRISPR gene-editing therapy.
"Although uncertainties about durability [of efficacy] and harm remain, both lovo-cel and exa-cel are likely to substantially improve quality and length of life among patients with SCD," ICER wrote in the report.
ICER said there was insufficient data to compare treatment benefits of lovo-cel and exa-cel against one another. However, when compared to standard care, which comprises the myelosuppressive agent hydroxyurea and blood transfusions, ICER said lovo-cel could likely provide at least an incremental net benefit for patients with severe sickle cell disease. ICER rated exa-cel slightly lower, characterizing the drug as likely to provide at least a comparable net benefit to standard care, given additional uncertainties around novel CRISPR therapies and the small number of patients treated to date.
An independent appraisal committee convened by ICER will review the report's evidence and cost-effectiveness estimates at a July 27 meeting.