Takeda
has announced ADZYNMA (recombinant ADAMTS13) has been approved by the US
FDA for chronic thrombotic thrombocytopenic purpura (cTTP) patients.
What is cTTP?
Takeda provides this answer.
cTTP is an ultra-rare, chronic, and debilitating clotting
disorder associated with life-threatening acute events and debilitating chronic
symptoms, or TTP manifestations. TTP has an estimated prevalence of 2-6
cases/million. The inherited form of the disease, cTTP, accounts for ≤5% of TTP
patients. It develops due to deficiency in ADAMTS13, a von Willebrand
factor (VWF) cleaving protease, which results in the accumulation of
ultra-large VWF multimers in the blood. The accumulation of ultra-large
VWF multimers leads to uncontrolled platelet aggregation and
adhesion. This can lead to abnormal clotting in the small blood vessels of
the body and is associated with microangiopathic hemolytic anemia and low
platelet levels (thrombocytopenia).
cTTP has both acute and chronic manifestations (including
stroke and cardiovascular disease) and when left untreated, acute TTP events
have a mortality rate of >90%. cTTP can also cause ongoing widespread
organ damage and other co-morbidities resulting from an ADAMTS13-deficient
state.
What will ADZYNMA do?
ADZYNMA provides patients with a treatment option that
replaces their deficient ADAMTS13 enzyme by injection instead of
plasmapheresis. This means a cTTP patient will not have to repeatedly receive
and react other people’s plasma. It means patients can have the process
provided locally or even at home and not have to go to a rare apheresis clinic.
The ADZYMNA site
indicates cTTP patients will have approximately 4- to 5-fold higher ADAMTS13
activity exposures compared to plasmapheresis.
What does this mean for aTTP patients?
There is no announcement yet, but since acquired TTP (aTTP)
patients are the other ≥95% of TTP patients, I am sure ADZYNMA processes will
be addressed for this group in the future. Imagine if an aTTP patient is tested
with a low ADAMTS13 and only needs a series of injections to recover. Will the
patients need Prednisone? Or the hard-to-get off label rituximab product?
Hopefully the process to provide recombinant ADAMTS13 will be extended to reduce the symptoms and suffering for all TTP patients.
