What happened

Shares of Editas Medicine (EDIT -4.58%) were up 13.9% this week as of the market close on Thursday. Most of this big gain came after a key announcement from the company on Wednesday about its phase 1/2 clinical study evaluating EDIT-101.

Editas said that an Independent Data Monitoring Committee (IDMC) gave a thumbs-up to enroll children with the rare genetic eye disorder Leber congenital amaurosis 10 (LCA10) in two pediatric cohorts of the study. 

So what

It's not surprising that the biotech stock spiked after the news. The IDMC endorsement is huge in that it appears to confirm an encouraging safety profile for EDIT-101, the company's lead pipeline candidate. If there were any serious reservations about the safety of the experimental gene-editing therapy, the IDMC wouldn't have cleared the way for children to be included in Editas' clinical trial.

DNA strands with a doctor in the background.

Image source: Getty Images.

Editas also had more good news to report. The company said that it has completed the dosing of patients in the adult mid-dose cohort of the clinical study of EDIT-101. It plans to move forward with the pediatric mid-dose cohort and adult high-dose cohort at the same time.

Now what

Editas expects to report initial data from its phase 1/2 study of EDIT-101 in September. The company plans to begin dosing patients in its pediatric mid-dose and adult high-dose cohorts of the study this summer.