Dr. Eric Hoffman of the Children’s National Medical Center predicts that individualized molecular therapies will be medicine’s next big innovation, but only if the FDA revises its regulatory processes.
In a recent edition of the New England Journal of Medicine, Dr. Hoffman shares the results of a clinical trial involving a new treatment for Duchenne muscular dystrophy (MD) which he believes provides a proof-of-concept for personalized molecular medicine.
The study involves application of a nucleic acid drug called PRO051. The drug shows promise in restoring the expression of dystrophin, a protein linked to healthy muscle tissue. PRO051 was shown to reactivate dystrophin protein production in small areas of muscle tissue at the injection site in MD patients.
“Dozens of specific sequences will be required for effectively treating the majority of patients with Duchenne muscular dystrophy,” says Hoffman. Implementation of the ‘exon-skipping’ approach described in the study will also require proof that long-term delivery is not toxic.
In order to advance this particular treatment, currently in its earliest stages, the FDA regulatory pathway will need to be reevaluated: these DNA-like drugs are tailored to the patient being treated – making them incompatible with existing approval processes.
For example, rodent and monkey studies, the current standard in drug-toxicity evaluation, are inappropriate since animals do not have the same DNA target sequences as humans.
Hoffman envisions the FDA treating molecular medicine as a separate class of drugs, rather than requiring individual testing for hundreds of different DNA sequences.
“The patients and their families are crossing their fingers that the drug’s overall chemistry can be shown to be safe,” says Hoffman.