Surotomycin versus vancomycin for Clostridium difficile infection: Phase 2, randomized, controlled, double-blind, non-inferiority, multicentre trial.

OBJECTIVES: Clostridium difficile infection (CDI) is a major public health concern. Treatment with commonly prescribed antibiotics is associated with high rates of recurrence after initial cure. Here, we present the efficacy and safety of surotomycin, an orally administered, minimally absorbed, selective bactericidal cyclic lipopeptide, compared with vancomycin, in patients with CDI. METHODS: In this Phase 2, randomized, controlled, double-blind, non-inferiority, multicentre trial, participants received surotomycin 125 mg twice daily, surotomycin 250 mg twice daily or vancomycin 125 mg four times daily for 10 days. The primary efficacy outcome was clinical response at end of treatment. The registration number of the study on clinicaltrials.gov is NCT01085591. RESULTS: Clinical cure rates were similar among treatment groups (92.4% for surotomycin 125 mg twice daily, 86.6% for surotomycin 250 mg twice daily and 89.4% for vancomycin). Recurrence rates were 27.9% for surotomycin 125 mg twice daily, 17.2% for surotomycin 250 mg twice daily and 35.6% for vancomycin. The lower recurrence rate with surotomycin 250 mg twice daily versus vancomycin was statistically significant (P = 0.035). Recurrence rates were statistically similar between the surotomycin dose groups (P = 0.193). Rates of sustained clinical response at end of study were 66.7% for surotomycin 125 mg twice daily, 70.1% for surotomycin 250 mg twice daily and 56.1% for vancomycin. Incidence of adverse events was similar among treatment arms. CONCLUSIONS: Recurrence rates of CDI were lower with surotomycin with higher sustained clinical response rates compared with vancomycin, both of which may offer potential clinical benefits.

Randomized controlled trial of the safety and efficacy of Daptomycin versus standard-of-care therapy for management of patients with osteomyelitis associated with prosthetic devices undergoing two-stage revision arthroplasty.

The prevalence of Staphylococcus aureus causing prosthetic joint infection (PJI) supports investigation of higher doses of daptomycin in the management of PJI. This was a prospective, randomized controlled trial studying safety and efficacy of daptomycin (6 and 8 mg/kg of body weight) compared with standard-of-care therapy for PJI. This open-label study randomized 75 patients undergoing 2-stage revision arthroplasty to daptomycin at 6 or 8 mg/kg or a comparator (vancomycin, teicoplanin, or semisynthetic penicillin). After prosthesis removal, patients received 6 weeks of antibiotic treatment and a 2- to 6-week antibiotic-free period before implantation of a new prosthesis. Test of cure (TOC) was within 1 to 2 weeks after reimplantation. The primary objective was evaluation of creatine phosphokinase (CPK) levels. Secondary objectives were clinical efficacy and microbiological assessments. Of 73 CPK safety population patients, CPK elevation of >500 U/liter occurred in 4 of 25 (16.0%) (daptomycin, 6 mg/kg) and 5 of 23 (21.7%) (daptomycin, 8 mg/kg) daptomycin-treated patients and 2 of 25 (8.0%) comparator patients. Adverse-event rates were similar among daptomycin and comparator groups. Among modified intent-to-treat patients at TOC, clinical success rates were 14 of 24 (58.3%) for 6 mg/kg daptomycin, 14 of 23 (60.9%) for 8 mg/kg daptomycin, and 8 of 21 (38.1%) for the comparator. Overall microbiological success at TOC was 12 of 24 (50.0%) for 6 mg/kg daptomycin, 12 of 23 (52.2%) for 8 mg/kg daptomycin, and 8 of 21 (38.1%) for comparator patients. In conclusion, daptomycin at 6 and 8 mg/kg given for up to 6 weeks was safe and appeared to be effective in managing staphylococcal PJI using a 2-stage revision arthroplasty technique in a total of 49 patients.

Pharmacokinetics of surotomycin from phase 1 single and multiple ascending dose studies in healthy volunteers.

BACKGROUND: Surotomycin, a novel, orally administered, cyclic, lipopeptide antibacterial in development for the treatment of Clostridium difficile-associated diarrhea, has demonstrated minimal intestinal absorption in animal models. METHODS: Safety, tolerability, and plasma pharmacokinetics of single and multiple ascending oral doses (SAD/MAD) of surotomycin in healthy volunteers were characterized in two randomized, double-blind, placebo-controlled, phase 1 studies. RESULTS: Participants were sequentially enrolled into one of four SAD (500, 1000, 2000, 4000 mg surotomycin) or three MAD (250, 500, 1000 mg surotomycin twice/day for 14 days) cohorts. Ten subjects were randomized 4:1 into each cohort to receive surotomycin or placebo. Surotomycin plasma concentrations rose as dose increased (maximum plasma concentration [Cmax]: 10.5, 21.5, 66.6, and 86.7 ng/mL). Systemic levels were generally low, with peak median surotomycin plasma concentrations observed 6-12 h after the first dose. In the MAD study, surotomycin plasma concentrations were higher on day 14 (Cmax: 25.5, 37.6, and 93.5 ng/mL) than on day 1 (Cmax: 6.8, 11.0, and 21.1 ng/mL for increasing doses), indicating accumulation. In the SAD study, <0.01% of the administered dose was recovered in urine. Mean surotomycin stool concentration from the 1000 mg MAD cohort was 6394 µg/g on day 5. Both cohorts were well tolerated with all adverse events reported as mild to moderate. CONCLUSION: Both SAD and MAD studies of surotomycin demonstrated minimal systemic exposure, with feces the primary route of elimination following oral administration; consistent with observations with similar compounds, such as fidaxomicin. Results of these phase 1 studies support the continued clinical development of surotomycin for the treatment of Clostridium difficile-associated diarrhea. TRIAL REGISTRATION: NCT02835118 and NCT02835105 . Retrospectively registered, July 13 2016.

Safety of daptomycin in patients completing more than 14 days of therapy: results from the Cubicin® Outcomes Registry and experience.

Patients with complicated infections may receive daptomycin for extended periods. This retrospective analysis was conducted to describe the safety profile of daptomycin in patients completing >14 days of therapy. In the Cubicin(®) Outcomes Registry and Experience (CORE(®)) 2005-2009, a retrospective, multicentre, observational registry, patients completing >14 days of daptomycin were studied. Investigators assessed adverse events (AEs) using ICH-E2A definitions of seriousness/severity ≤30 days after completing daptomycin. AEs were grouped by onset at ≤14, 15-28 and >28 days after starting daptomycin. In total, 2263 patients received >14 days of daptomycin. The most common indications were complicated skin and skin-structure infection (25.5%) and osteomyelitis (21.7%). Regarding AEs, 205 patients (9.1%) experienced AEs with an onset ≤14 days of therapy, 168 (7.4%) between 15-28 days and 108 (4.8%) >28 days; a total of 389/2263 patients experienced 814 AEs. The most common AE was increased blood creatine phosphokinase (CPK), occurring in 49 patients (2.2%) during ≤14 days of therapy, 32 (1.4%) between 15-28 days and 10 (0.4%) >28 days. In 183/2263 patients (8.1%), 264 AEs were possibly related to daptomycin. Serious AEs occurred in 153/2263 patients (6.8%). Eighty-nine (3.9%) of 2263 patients had daptomycin discontinued due to AEs, with 36 discontinued due to increased CPK. The overall mortality rate was 63/2263 (2.8%); 4 patients died of a possibly related AE. The most common AEs with onset <14 days were similar to those occurring between 15-28 days and >28 days. Daptomycin appears to be safe in patients treated for >14 days.