Lumos delays key hormone deficiency readout as COVID bites

Lumos Pharma has delayed top-line data from its phase 2 pediatric growth hormone deficiency (PGHD) trial to the second half of 2023. The biotech blamed the delay on the impact of COVID-19 restrictions on the pace of site initiation and enrollment, particularly at sites outside of the U.S.

Texas-based Lumos was looking to overseas sites to enroll subjects faster than its U.S. centers. So far, the ex-U.S. part of the trial is lagging behind expectations. The ClinicalTrials.gov listing for the study features 34 sites, 25 of which are in the U.S. Three of the ex-U.S. sites are in Australia, which has reimposed restrictions to curb the spread of the COVID-19, and one of the other six was yet to start recruiting as of July 8. Lumos aims to have 40 to 50 sites but initiation is going slower than hoped. 

The slow pace of site initiation and enrollment has forced Lumos to push back the targeted delivery of the six-month primary outcome data from mid-2022 to the second half of 2023. Lumos’ shares slipped in the wake of the news.

Lumos is running the phase 2 OraGrowtH210 trial to compare the effect of its oral small molecule LUM-201 to Novo Nordisk’s Norditropin injection. The non-peptide agonist of the ghrelin receptor, which originated at Merck, is designed to promote secretion of growth hormone from the pituitary gland and thereby free PGHD patients from injectable treatments.

The mechanism of action has caught the attention of the FDA. Lumos disclosed news of the delay alongside details of the FDA’s request for an extension of the phase 2 trial to 12 months because of the novel mechanism of action. 

The planned second half of the study mirrors the first six months of a proposed long-term extension study. The FDA has put the long-term extension study on partial clinical hold until more OraGrowtH210 efficacy data are available. Lumos doesn’t expect the protocol changes to delay its move into phase 3. 

“Though the FDA’s request for a six-month extension to our OraGrowtH210 Trial was unexpected, we are confident that our trial protocol changes will both add impactful data and meet the FDA’s request,” Lumos CEO Rick Hawkins said in a statement.

Lumos is also extending a study of the pharmacokinetic and pharmacodynamic effects of LUM-201 in PGHD patients. That trial, which got underway last month, will now track patients for 12 months as well, although a data analysis will still happen at six months as planned.