FDA clears Beam’s IND for base editing therapy in AATD

The U.S. FDA has cleared Beam Therapeutics’ investigational new drug (IND) application for BEAM-302 for the treatment of alpha-1 antitrypsin deficiency (AATD), allowing the company to expand its clinical trial to the U.S.

Earlier this month, Beam shared initial safety and efficacy data from the ongoing phase 1/2 trial outside of the U.S. and is now poised to expand patient enrollment and activate new clinical sites in the U.S. Part A of the trial is designed to evaluate AATD patients with lung disease, and part B will evaluate AATD patients with mild to moderate liver disease with or without lung disease. 

The company's regulatory clearance for BEAM-302 now spans six countries — U.S., UK, New Zealand, Australia, the Netherlands and Ireland. This marks the second IND for Beam's in vivo base editing programs in the U.S.

AATD is an inherited genetic disorder — with no approved curative treatments — that affects the lungs and/or liver, leading to early onset emphysema and liver disease. A number of genetic mutations cause AATD, but it’s estimated that approximately 100,000 individuals in the U.S. have the PiZZ genotype.

Patients with the PiZZ genotype have very low circulating levels of functional alpha-1 antitrypsin (AAT) protein, all of which is the mutant form, known as Z-AAT, which accumulates and causes liver toxicity. By correcting the PiZ mutation at the DNA level, BEAM-302 has the potential to be a one-time therapy that simultaneously reduces the amount of Z-AAT in circulation, generates therapeutic levels of corrected protein (M-AAT), and increases total and functional AAT in circulation above the 11µM protective threshold, thereby addressing the underlying pathophysiology of both the liver and lung disease.