Oct 10 (Reuters) - The U.S. Food and Drug Administration

on Friday approved labeling changes for Johnson & Johnson ( JNJ )

and its partner Legend Biotech's ( LEGN ) blood cancer

therapy to include a boxed warning for a potentially fatal

gastrointestinal condition.

The FDA said it received reports that some patients treated

with Carvykti developed a serious gut inflammation called

IEC-EC, which in some cases led to life-threatening

complications like bowel perforation and sepsis.

Reports were received from clinical trials and postmarketing

adverse event data, the FDA said.

IEC-EC is a form of inflammation of the intestines triggered

by the immune system. It was observed weeks to months after

CAR-T therapy treatment with Carvykti in both clinical trials

and after approval, the regulator said.

Symptoms included persistent diarrhea, stomach pain and

weight loss, often requiring intensive care and

immune-suppressing drugs.

Carvykti was first approved in February 2022 and received

expanded approval in April 2024 for adults with relapsed or

refractory multiple myeloma who had received at least one prior

line of therapy.

Multiple myeloma is an incurable blood cancer that affects a

type of white blood cell called plasma cells, found in the bone

marrow.

The FDA also updated the "clinical studies" section of the

drug's prescribing information to include overall survival data

from the late-stage trial.

The interim data of the late-stage study showed a

statistically significant improvement in survival for patients

receiving Carvykti compared to those on standard therapy, with a

median follow-up of 33.6 months.

Despite the new safety concerns, the FDA said the overall

benefit of Carvykti continues to outweigh the risks for its

approved use.