March 20 (Reuters) - Roche has stopped

developing its experimental drug for two rare muscle diseases

after it failed to show meaningful benefits, the Swiss drugmaker

said in community letters.

Here are some details:

* In the letters, dated March 19, the company said it would

no longer pursue the drug, emugrobart, for spinal muscular

atrophy, or SMA, and facioscapulohumeral muscular dystrophy,

known as FSHD.

* Both the conditions are rare genetic diseases that cause

progressive muscle weakness and can severely limit a person's

ability to walk and carry out daily tasks.

* Emugrobart is designed to block myostatin, a protein that

naturally limits muscle growth.

* Roche said the drug showed a favorable safety profile and

reduced mature myostatin levels, but this did not translate into

meaningful gains in muscle growth or function across study

participants.

* The results were not strong or consistent enough to move

into late-stage trials, the company said.

* In SMA, emugrobart was tested in combination with

risdiplam and compared against risdiplam alone, while in FSHD it

was tested against a placebo.

* The mid-stage trial development of emugrobart for obesity,

however, will continue as planned, Roche said.