The US Food and Drug Administration
approved two gene therapies for the treatment of sickle cell disease or SCD in
patients aged 12 years and above.
Casgevy, a cell-based gene therapy, is
approved for the treatment of sickle cell disease in patients 12 years of age
and older with recurrent vaso-occlusive crises. Casgevy is the first
FDA-approved therapy utilising CRISPR/Cas9, a type of genome editing
technology.
Lyfgenia is a cell-based gene therapy
that uses a lentiviral vector for genetic modification and is approved for the
treatment of patients aged 12 years and above with sickle cell disease and a
history of vaso-occlusive events, according to FDA statement.
FDA stated, “With Lyfgenia, the patient’s
blood stem cells are genetically modified to produce HbAT87Q, a gene-therapy-derived
haemoglobin that functions similarly to haemoglobin A, which is the normal
adult haemoglobin produced in persons not affected by sickle cell disease.”
“Red blood cells containing HbAT87Q have
a lower risk of sickling and occluding blood flow. These modified stem cells
are then delivered to the patient,” it added.
FDA’s Center for Biologics Evaluation
and Research director Peter Marks called these approvals an important medical
advance. The FDA granted approval of Casgevy to Vertex Pharmaceuticals Inc and
approval of Lyfgenia to Bluebird Bio Inc.
Marks said, “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.”
He added, “Today’s actions follow rigorous
evaluations of the scientific and clinical data needed to support approval,
reflecting the FDA’s commitment to facilitating development of safe and
effective treatments for conditions with severe impacts on human health.”
Sickle cell disease is a group of
inherited blood disorders affecting approximately 100,000 people in US. It is
most common in African Americans and, while less prevalent, also affects
Hispanic Americans, according to the FDA. The primary problem in sickle cell
disease is a mutation in haemoglobin.
This mutation causes red blood cells to
develop a crescent or “sickle” shape. These sickled red blood cells restrict
the flow in blood vessels and restrict oxygen delivery to the tissues of the
body, leading to severe pain and organ damage called vaso-occlusive events
(VOEs) or vaso-occlusive crises (VOCs).
The recurrence of these events or crises
can cause life-threatening disabilities and/or early death, according to the
FDA.
ANI
