Omadacycline Non-Inferior to Linezolid in ABSSSI Patients With CKD

Omadacycline is a novel, broad-spectrum aminomethylcycline related to tetracyclines; the OASIS phase 3 trial investigated whether it was non-inferior to linezolid.

This article is written live from ID Week 2017 Annual Meeting in San Diego, CA. MPR will be reporting news on the latest findings from leading experts in infectious diseases. Check back for more news from IDWeek 2017.

SAN DIEGO—Among patients with chronic kidney disease (CKD), omadacycline (OMC) was a well-tolerated treatment of acute bacterial skin and skin structure infections (ABSSSI), with a safety profile similar to that seen in patients without CKD, according to findings reported at IDWeek 2017.

“IV to once-daily oral omadacycline was effective and well tolerated for treating ABSSSI in patients with CKD-0/1 and CKD-2/3,” reported lead study author Thomas M. File Jr., MD, MSc, MACP, FIDSA, FCCP, of Summa Health System, Akron, OH, and colleagues. “No differences in efficacy at early clinical response endpoint or post-treatment evaluation were observed between omadacycline and linezolid treatment.”

Treatment-emergent adverse events (TEAEs) for omadacycline were “generally comparable” with linezolid, Dr. File added.

Tetracycline and other antibiotics are associated with renal insufficiency. OMC is a broad-spectrum aminomethylcycline antibiotic related to tetracyclines, Dr. File said. “In OASIS, a Phase 3 ABSSSI study, intravenous (IV)-to-oral OMC was non-inferior to IV-to-oral linezolid (LZD),” he noted.

The researchers reported OASIS study efficacy and safety data for OMC compared to LZD among patients with stage 1 CKD (CKD-1; GFR ≥90mL/min) or stage 2/3 CKD (CKD-2/3; GFR 30–89mL/min). 

An intention-to-treat population of 655 patients were randomly assigned 1:1 to receive OMC (100mg IV q12h × 2 doses followed by 100mg IV every 24 hours), or to LZD. (After at least 3 days on IV therapy, patients could transition to oral OMC [300mg every 24 hours] or oral LZD.) Early clinical response (ECR) was assessed 48 to 72 hours after IV therapy.

“ECR rates in OMC- and LZD-treated CKD-1 patients were slightly higher than that in CKD-2/3 patients,” Dr. File noted. “At PTE [post-treatment evaluation], clinical responses with OMC and LZD were higher than ECR in CKD-2/3.” Post-treatment clinical success was “numerically higher” for OMC than LZD in all CKD categories.

“There were minor variations in liver chemistry TEAEs between regimens across subgroups,” Dr. Fine noted. “Seventy-nine percent of patients in each treatment group had ABSSSI considered related to IV drug use. All infusion site extravasation events were mild and typically due to difficulty in finding reliable venous access sites.”

“Overall, baseline pathogens were generally similar across most subgroups and infection types,” Dr. Fine reported. “Staphylococcus aureus was the most common pathogen, and MRSA was present in up to 39% of patients.”

CKD-2/3 patients had a higher proportion of mixed wound-infection pathogens, the researchers found.

For continuous infectious disease news coverage from the IDWeek 2017, check back to MPR’s IDWeek page for the latest updates.


File TM, Cure-Bolt N, Chitra S, Tzanis E, McGovern P. Efficacy and Safety of Omadacycline in Chronic Kidney Disease (CKD) Patients with Acute Bacterial Skin and Skin Structure Infections (ABSSSI): A Subgroup Analysis from the OASIS Tria. Poster presented at IDWeek; October 4–8, 2017; San Diego, CA.