United States – The US health regulator has not cleared gene therapy by Rocket Pharmaceuticals (RCKT. O) to treat a deadly and rare pediatric autoimmune syndrome that attacks the immune system.
New Jersey-based company stocks dropped more than 13% to USD 18.51 premarket on the news.
FDA Requests Additional Information
In a so-called complete-response letter, the FDA requests further information concerning specific procedures regarding the gene therapy known as Kresladi, as reported by Reuters.
Rocket still required initial approval from the agency to apply the therapy to affectec patients with severe leukocyte adhesion deficiency-I (LAD-I).
In these patients, the absence of functional protein produced due to mutation in the protein-encoding ITGB2 gene does not allow the white blood cells to adhere to the blood vessel walls of the site of infection. It could result in life-threatening immune conditions and repeated infections within the body.
In February, it had also added more time to decide whether to approve the therapy as it considers similar data for other processes in the gene therapy.
Analysts Weigh In
The analysts at TD Cowen had then said that this looked more and more like an FDA bandwidth problem and not something that was wrong at the company.
This came after Rocket said on Friday that it had a meeting with the FDA officials to determine the information that they wanted for a fast approval of the therapy.
Company Efforts and FDA Delays
The company recently filed an application for marketing this drug based on data from a Phase II trial in which nine patients all survived for at least 12 months after infusion. The therapy also reduced infections and had other related benefits, as reported by Reuters.
LAD-I directly affects about 800 to 1000 people in the United States and Europe, according to the company’s own figures.
At the moment, the treatment for the condition is only done by what is known as a bone marrow transplant, a procedure which is usually not easily accessible and is very risky.