Philley, Julie V.

ABSTRACT Infections due to nontuberculous mycobacteria (NTM) continue to increase in prevalence, leading to problematic clinical outcomes. Omadacycline (OMC) is an aminomethylcycline antibiotic with FDA orphan drug and fast-track designations for pulmonary NTM infections, including Mycobacteroides abscessus (MAB). This multicenter retrospective study across 16 U.S. medical institutions from January 2020 to March 2023 examined the long-term clinical success, safety, and tolerability of OMC for NTM infections. The cohort included patients aged ≥18 yr, who were clinically evaluable, and` had been treated with OMC for ≥3 mo without a previous diagnosis of cystic fibrosis. The primary outcome was 3 mo clinical success, with secondary outcomes including clinical improvement and mortality at 6- and 12 mo, persistence or reemergence of infection, adverse effects, and reasons for OMC utilization. Seventy-five patients were included in this analysis. Most patients were female (48/75, 64.0%) or Caucasian (58/75, 77.3%), with a median (IQR) age of 59 yr (49–67). Most had NTM pulmonary disease (33/75, 44.0%), skin and soft tissue disease (19/75, 25.3%), or osteomyelitis (10/75, 13.3%), and Mycobacterium abscessus (60/75, 80%) was the most commonly isolated NTM pathogen. The median (IQR) treatment duration was 6 mo ( 4 – 14 ), and the most commonly co-administered antibiotic was azithromycin (33/70, 47.1%). Three-month clinical success was observed in 80.0% (60/75) of patients, and AEs attributable to OMC occurred in 32.0% (24/75) of patients, leading to drug discontinuation in 9.3% (7/75).

Abstract Background Multi-drug resistant (MDR) pathogens are a continuously evolving threat for which there are limited effective treatment modalities. Omadacycline (OMC) is a novel oral and intravenously administered aminomethylcycline with potent in-vitro activity against MDR gram-negative and gram-positive pathogens. Post-marketing data investigating its potential place in the antibiotic armamentarium is limited. This study aimed at describing the clinical success and tolerability of patients receiving OMC for various infections. Methods This was a multicenter, retrospective, observational study conducted from January 2020 to March 30, 2022. We included all patients ≥ 18 years of age that received OMC for any infection not related to Mycobacterium spp. for ≥72 hours. The primary outcome was clinical success at 30 days, defined as survival, the absence of persistence or re-emergence of infection during or after therapy, and the absence of escalation or alteration of OMC. Incidence of adverse effects while on OMC and reasons for OMC utilization were also analyzed. Results This analysis included 19 patients from 10 distinct academic centers. The median age was 50 years (IQR, 37-63), 58% were male, 63% were Caucasian, and the median APACHE II, Charlson and SOFA scores were 10 (IQR 5-12.5), 4 (IQR 2-6.3), and 1 (IQR 0 – 2.25), respectively. Most patients had a bone and joint (8/19, 42.1%) or intra-abdominal infections (4/19, 21.1%), all with positive cultures. Eight patients (44.1%) had a polymicrobial infection and 4 (22.2%) had bacteremia. The most common pathogens encountered were Carbapenem-resistant A. baumannii (5/19, 27.8%), E. coli (5/19, 27.8%), Vancomycin-resistant Enterococcus spp. (4/19, 22.2%), and K. pneumoniae (3/19, 16.7%). Clinical success was observed in 14 patients (74%) and 7 (36.8%) received combination therapy. Adverse drug reactions were reported in 3 patients (15.8%) and of those patients, none discontinued therapy. Reasons for prescribing OMC were mostly attributed to oral availability (12/14, 85.7%) and resistance to other agents (7/14, 50%). Conclusion OMC demonstrated clinical effectiveness and safety against a large number of MDR pathogens. More robust, prospective, comparative studies are needed to confirm our preliminary findings. Disclosures P. Brandon Bookstaver, PharmD, Spero Therapeutics: Advisor/Consultant.

Abstract Background Nontuberculous mycobacteria (NTM) are resistant to numerous antibiotics and lead to significant morbidity and mortality. Omadacycline (OMC) is an aminomethylcycline antibiotic that is Food and Drug Administration-approved for acute bacterial skin and skin structure infections and community-acquired bacterial pneumonia. Furthermore, OMC has shown in vitro activity against NTM. Given that real-world evidence is lacking, our primary objective was to evaluate the clinical success and tolerability of OMC when used for a variety of NTM infections. Methods This was a multicenter, retrospective, observational study conducted from January 2020 to June 2021. We included all patients ≥ 18 years of age that received OMC of any indication for Mycobacterium spp. The primary outcome was clinical success, defined as a lack of all-cause mortality, lack of persistence or re-emergence of infection during or after therapy, and lack of alteration of OMC. Incidence of adverse effects potentially attributable to OMC and reasons for OMC utilization were also analyzed. Results A total of 31 patients were included from 12 geographically distinct academic health systems (median age: 57 (IQR, 45-63) years; 45% male; 81% Caucasian). The majority of isolated pathogens were Mycobacterium abscessus complex (84%) and of those with subspeciation performed (54%), the majority (86%) were subsp. abscessus. The primary infections were of pulmonary origin (67%) and the median (IQR) duration of OMC therapy was 5.3 (3.2-9.4) months. Most isolates did not have OMC susceptibility conducted (87%), while the majority did for tigecycline (90%). Clinical success was reported in 81% of the population. Most patients were on combination antimicrobial therapy, and 39% of patients reported an adverse effect while on OMC (58% gastrointestinal distress). The majority of patients were prescribed OMC due to ease of administration (61%) and antimicrobial resistance to previous antibiotics (42%). Conclusion OMC may be a potential option for the therapy of NTM infections. Prospective, randomized clinical trials are needed to confirm our preliminary findings. Disclosures Julie V. Philley, MD, Paratek Pharmaceuticals (Advisor or Review Panel member)Paratek Pharmaceuticals, Inc. (Consultant) Michael P. Veve, Pharm.D., Cumberland (Grant/Research Support)Paratek Pharmaceuticals (Research Grant or Support) Michael J. Rybak, PharmD, MPH, PhD, Paratek Pharmaceuticals (Research Grant or Support)

Abstract Twelve patients were treated with omadacycline (OMC) as part of a multidrug regimen for Mycobacterium abscessus. The majority of infections were of pulmonary origin (7/12; 58.3%). The median (interquartile range) duration of OMC was 6.2 (4.2–11.0) months. Clinical success occurred in 9/12 (75.0%) patients. Three patients experienced a possible adverse effect while on therapy.

Abstract Background Omadacycline (OMC) is an aminomethylcycline antibiotic in the tetracycline class that has been Food and Drug Administration-approved for acute bacterial skin and skin structure infections and community-acquired bacterial pneumonia. OMC has been shown to have potent in vitro activity against a broad-spectrum of Gram-positive and Gram-negative organisms, as well as Nontuberculous Mycobacteria (NTM). Due to it’s unique activity and availability as an oral agent, off-label use of OMC has been increasing. We evaluated the real-world effectiveness and safety of OMC for a variety of infections. Methods This was a multicenter, retrospective, observational study that was conducted from January 2020 to June 2020. We included all patients ≥ 18 years of age that received OMC for ≥ 72 hours for any indication and/or pathogen. The primary outcome was clinical success, defined as a lack of 30-day (non-NTM) or 90-day (NTM) mortality or microbiologic recurrence and absence of therapy escalation or alteration. Reasons for OMC utilization and incidence of potential adverse effects attributable to OMC were also analyzed. Results A total of 18 patients were included from six geographically distinct academic health systems (median age: 56 (IQR, 49-60.5) years; 61% male; 72% Caucasian). The majority of OMC use was in NTM (61%; 100% Mycobacterium abscessus) and in Acinetobacter baumannii (22%) for bone/joint (39%) and respiratory tract (33%) infections. OMC was used primarily in the outpatient setting alone (83%) and most isolates did not have OMC susceptibility conducted (89%). Clinical success was reported in 83% of the total population (71% non-NTM and 91% NTM). The majority of patients were prescribed OMC due to antimicrobial resistance to previous antibiotic(s) (61%) and/or due to OMC’s availability as an oral agent (44%). Three patients experienced side effects while on therapy (serum creatinine elevation, AST/ALT increase, and gastrointestinal distress). Conclusion OMC appears to be effective and well-tolerated for a variety of infections caused by various pathogens, including M. abscessus and A. baumannii. Disclosures Michael J. Rybak, PharmD, MPH, PhD, Paratek (Grant/Research Support)