FDA Updates for Week of October 3, 2022

The FDA uses real-world data to show how Boostrix prevents infections in infants. The agency also approves a label expansion for Oxlumo, a new administration method for Trogarzo, and accepts an sBLA for Takhzyro. In COVID-19 news, Eiger won’t submit EUA for COVID-19 treatment. Additionally, an OIG reports finds many accelerated approvals have delayed confirmatory trials.

Real-world data confirms Boostrix used in third trimester prevents infections in infants.

The FDA has approved Boostrix for immunization during the third trimester of pregnancy to prevent pertussis, commonly known as whooping cough, as a way to prevent infection in infants younger than two months of age.

Boostrix is composed of tetanus toxoid, reduced diphtheria toxoid and acellular pertussis vaccine (Tdap). It was initially approved by the FDA in 2005 as a single dose for booster immunization against tetanus, diphtheria and pertussis in people 10 through 18 years of age. Later the FDA also approved Boostrix to include use in people 19 years of age and older and to include use of an additional dose 9 years or more after the initial dose of a Tdap vaccine.

The FDA’s approval of Boostrix has always included its use during pregnancy to protect the vaccinated individual. Today’s approval is specific to use in pregnancy to prevent pertussis in infants younger than 2 months of age. Since 2012, the CDC has recommended the use of Tdap vaccines during the third trimester of each pregnancy.

Regulators assessed the effectiveness of Boostrix to prevent pertussis among infants using a re-analysis of data from an observational case-control study of Tdap vaccine effectiveness.

FDA approves label expansion for Oxlumo.

The FDA has approved a supplemental new drug application for Alnylam Pharmaceuticals’ Oxlumo (lumasiran) to treat patients with primary hyperoxaluria type 1 (PH1), a rare and serious metabolic disease that often presents with kidney stones. It is caused by mutations in the AGXT gene that leads to the buildup of oxalate, which is filtered through the kidneys. The disease affects less than 5,000 people in the United States.

Oxlumo is an RNAi therapeutic administered via subcutaneous injection and is indicated to lower plasma oxalate levels and urinary oxalate levels in pediatric and adult patients. This approval adds lowering plasma oxalate levels to the indication. The therapy harnesses RNA interference, a natural cellular process of gene silencing. The FDA approved Oxlumo in November 2020 for the treatment of PH1 to lower urinary oxalate levels in pediatric and adult patients.

FDA approves new administration method for Trogarzo in HIV.

The FDA has approved Thera Technologies’ “push” administration of Trogarzo (ibalizumab-uiyk) to treat patients with human immunodeficiency virus type 1 (HIV-1) infection in heavily treatment-experienced adults. Trogarzo was approved for administration by intravenous (IV) push, a method in which the undiluted medication is pushed by syringe for faster administration into the body’s circulation. This method reduces the maintenance dose from a 15-minute IV infusion to a 30-second, undiluted IV push every two weeks.

The FDA originally approved Trogarzo, a long-acting monoclonal antibody, in March 2018 to be administered intravenously as a single loading dose followed by a maintenance dose every two weeks. Trogarzo is also being studied for intramuscular injection administration in the continuation of the TMB-302 study. The study is now fully enrolled, with the last patient visit scheduled for November 2022.

FDA accepts BLA for Takhzyro in young children with HAE.

The FDA has accepted a supplemental biologics license application (sBLA) for the potential expanded use of Takeda’s Takhzyro (lanadelumab-flyo) to prevent attacks of hereditary angioedema (HAE) in pediatric patients 2 to <12 years of age. Currently, children with HAE under the age of 6 have no approved prophylaxis treatment. If approved, Takhzyro could potentially become the first treatment for this population. The FDA has granted priority review and indicated a decision is expected in the first half of 2023.

Takhzyro is currently approved in patients 12 years and older to prevent attacks of hereditary angioedema (HAE), a rare disease that cause recurrent episodes of swelling of the limbs, face, intestinal tract and airway. Symptoms of hereditary angioedema typically begin in childhood and worsen during puberty. On average, untreated individuals have an attack every one to two weeks, and most episodes last for about three to four days.

Eiger will not submit EUA for COVID-19 treatment.

A month after the FDA said it was requiring additional data on Eiger BioPharmaceuticals’ request for emergency use authorization (EUA) of peginterferon lambda to treat patients with mild-to-moderate COVID-19, the pharma maker said it will not submit the EUA.

Following a pre-EUA information exchange with the FDA regarding the phase 3 TOGETHER study of peginterferon lambda for COVID-19, the agency indicated in September that it was not yet able to determine whether the criteria for the submission of an application and issuance of an EUA are likely to be met, Eiger said in a press release at the time.

Eiger officials said they are evaluating next steps for this program in the United States, as well as ex-U.S. emergency use authorization pathways and strategic options for continued development of peginterferon lambda for COVID-19 and other respiratory viral infections.

Eiger licensed worldwide rights to peginterferon lambda, an investigational late-stage, first-in-class, type 3 interferon (IFN) that stimulates immune responses that are critical for the development of host protection during viral infections, from Bristol-Myers Squibb.

OIG: one-third of accelerated approvals have delayed confirmatory trials.

Medicare and Medicaid spent more than $18 billion from 2018 to 2021 for 18 drugs granted accelerated approval that have incomplete confirmatory trials past their original planned completion date, according to new analysis by the Office of Inspector General, the U.S. Department of Health and Human Services. The OIG estimated that Medicare Part B and Part D spent more than $14 billion, and Medicaid spending —for both fee-for-service and managed care— for these drugs was nearly $3.6 billion.

OIG officials indicated this review stemmed from concern that the regulator’s oversight of accelerated approval was lax. Accelerated approvals often use surrogate endpoints that predict clinical benefit, but don’t measure clinical benefit. The pathway is meant to provide earlier access to drugs to treat serious diseases. Companies are required to conduct confirmatory trials to verify clinical benefit and to provide a timeline for completion.

Since the accelerated approval pathway began in 1992, 278 drug applications have been granted accelerated approval by the FDA’s Center for Drug Evaluation and Research (CDER). Of these applications, 104 have incomplete confirmatory trials. Of those 104, 34% (35 of 104) have at least one trial past its original planned completion date. Additionally, 13% of all accelerated approval drug applications have been withdrawn, half of which were withdrawn since January 2021.

Four drug applications have confirmatory trials that are significantly late — ranging from more than five years to nearly 12 years past their original completion dates. OIG researchers found that of these four drugs that were significantly late with confirmatory trials, Proamatine (midodrine hydrochloride) had the highest Medicare Part D estimated spending at $142 million and Makena (hydroxyprogesterone caproate) had the highest estimated Medicaid spending, nearly $700 million.