Aug 1 (Reuters) - Regeneron said on Friday the

U.S. Food and Drug Administration has once again declined to

approve its blood cancer therapy, this time in relation to

observations from the regulator's inspection at a third-party

manufacturing site.

The company was seeking approval for its drug odronextamab

to treat follicular lymphoma - a type of cancer that begins in

the lymph system, a part of the immune system - in patients

whose cancer has returned and who have received at least two

prior lines of treatment.

The regulator had first declined to approve the therapy in

March last year, seeking more data from enrollments in

dose-finding and confirmatory portions of trials testing it.

Regeneron said on Friday the latest FDA decision was due to

its inspection at contract manufacturer Catalent's Indiana site,

which was acquired by Danish drugmaker Novo Nordisk.

Catalent's Bloomington, Indiana facility is a fill-finish

site for Regeneron's Eylea HD and odronextamab, and handles the

final stages of drug preparation and packaging.

The observations at the inspection have also resulted in

delays to three applications for the high-dose version of its

eye disease drug Eylea, Regeneron said, adding that Novo has

been in communication with the FDA and expects to submit its

response next week.

There is clear frustration and exhaustion with the repeated

regulatory setbacks, said Cantor analyst Carter Gould.

Regeneron said the inspection was completed in mid-July and

it anticipates an expeditious resolution of the issues.

Odronextamab belongs to a class of treatments called

bispecific antibodies, which are designed to attach to a cancer

cell and an immune cell bringing them together so that the

body's immune system can kill the cancer.

The drug was approved by the European Commission in August

2024 to treat follicular lymphoma, and is branded as Ordspono in

the region.