Background Rezafungin, a novel, once-weekly echinocandin for the treatment of candidemia and/or invasive candidiasis (IC) was noninferior to caspofungin for day 30 all-cause mortality (ACM) and day 14 global cure in the phase 3 ReSTORE trial (NCT03667690). We conducted preplanned subgroup analyses for patients with a positive culture close to randomization in ReSTORE.Methods ReSTORE was a multicenter, double-blind, double-dummy, randomized trial in patients aged >= 18 years with candidemia and/or IC treated with once-weekly intravenous rezafungin (400 mg/200 mg) or once-daily intravenous caspofungin (70 mg/50 mg). This analysis comprised patients with a positive blood culture drawn between 12 hours before and 72 hours after randomization or a positive culture from another normally sterile site sampled between 48 hours before and 72 hours after randomization. Efficacy endpoints included day 30 ACM, day 14 global cure rate, and day 5 and 14 mycological response. Adverse events were evaluated.Results This analysis included 38 patients randomized to rezafungin and 46 to caspofungin. In the rezafungin and caspofungin groups, respectively, day 30 ACM was 26.3% and 21.7% (between-group difference [95% confidence interval], 4.6% [-13.7%, 23.5%]), day 14 global response was 55.3% and 50.0% (between-group difference, 5.3% [-16.1%, 26.0%]), and day 5 mycological eradication was 71.1% and 50.0% (between-group difference, 21.1% [-0.2%, 40.2%]). Safety was comparable between treatments.Conclusions These findings support the efficacy and safety of rezafungin compared with caspofungin for the treatment of candidemia and/or IC in patients with a positive culture close to randomization, with potential early treatment benefits for rezafungin. This preplanned subgroup analysis of the ReSTORE trial supports rezafungin efficacy and safety versus caspofungin for the treatment of candidemia and/or invasive candidiasis in patients with a positive culture close to randomization, who may represent patients with more serious infections. Graphical Abstract

Rezafungin is an echinocandin approved in the US and EU to treat candidaemia and/or invasive candidiasis. This post-hoc, pooled analysis of the Phase 2 STRIVE and Phase 3 ReSTORE trials assessed rezafungin versus caspofungin in patients with candidaemia and/or invasive candidiasis (IC) in the intensive care unit (ICU) at randomisation. STRIVE and ReSTORE were randomised double-blind trials in adults with systemic signs and mycological confirmation of candidaemia and/or IC in blood or a normally sterile site ≤ 96 h before randomisation. Data were pooled for patients in the ICU at randomisation who received intravenous rezafungin (400 mg loading dose then 200 mg once weekly) or caspofungin (70 mg loading dose then 50 mg once daily) for ≤ 4 weeks. Outcomes were Day 30 all-cause mortality (primary outcome), Day 5 and 14 mycological eradication, time to negative blood culture, mortality attributable to candidaemia/invasive candidiasis, safety, and pharmacokinetics. Of 294 patients in STRIVE/ReSTORE, 113 were in the ICU at randomisation (rezafungin n = 46; caspofungin n = 67). At baseline, 30

Invasive candidiasis/candidemia (IC/C) is associated with a substantial health economic burden driven primarily by prolonged hospital stay. The once-weekly IV echinocandin, rezafungin acetate, has demonstrated non-inferiority to caspofungin in the treatment of IC/C. This paper reports a post hoc pooled exploratory analysis of length of stay (LoS) for hospital and intensive care unit (ICU) stays in two previously published clinical trials (ReSTORE [NCT03667690] and STRIVE [NCT02734862], that compared rezafungin with daily IV caspofungin (stable patients in the caspofungin group who met relevant criteria could step down to fluconazole after 3 days or more). LoS outcomes were analysed descriptively in the pooled modified intention to treat (mITT) population (all patients who had a documented Candida infection in line with trial requirements and received at least one dose of study drug). In addition, to adjust for an imbalance between treatment groups in the proportion receiving mechanical ventilation at baseline, a generalised linear model with mechanical ventilation as a binary covariate was applied. Responses to an exploratory question in the phase 3 trial on possible earlier discharge with weekly rezafungin are also reported. 294 patients were included (rezafungin 139, caspofungin 155), of whom 126 (43

Abstract Background Factors including frailty and multimorbidity can affect candidaemia and/or invasive candidiasis (C/IC) treatment in older people.1 The current analysis explored data from C/IC patients aged ≥65 years who were treated with rezafungin or caspofungin in the STRIVE (Phase 2: NCT02734862) and ReSTORE (Phase 3: NCT03667690) clinical trials.2,3 Methods STRIVE and ReSTORE were double-blind, randomized studies. Adults with C/IC, diagnosed by systemic signs and mycological confirmation, received rezafungin once-weekly (Week 1: 400 mg; Weeks 2–4: 200 mg) or once-daily caspofungin (Day 1: 70 mg; Days 2–28: 50 mg) by IV injection for ≥14 days (≤4 weeks). Post hoc analysis examined pooled STRIVE/ReSTORE data for subjects aged ≥65 years. Safety outcomes included treatment emergent adverse events (TEAEs) and serious adverse events (SAEs) in subjects who received ≥1 dose of study drug (safety population). Day 30 all-cause mortality (ACM) and mycological response at Days 5 and 14 were examined for the modified intention-to-treat (mITT) population (subjects with mycological C/IC diagnosis within 96 h of randomization who received ≥1 study drug dose). Results The safety population included 132 subjects (rezafungin arm: 64; caspofungin arm: 68). The mITT population included 120 subjects (rezafungin arm: 57; caspofungin arm: 63). The most common TEAEs with rezafungin were hypokalaemia, diarrhoea, vomiting and anaemia (Table 1). Eight subjects reported rezafungin-related TEAEs and seven had caspofungin-related TEAEs. SAEs comprised one case each of first degree atrioventricular block (rezafungin arm) and acute liver injury (caspofungin arm). Day 30 ACM rate was 14.0% (rezafungin arm) and 31.7% (caspofungin arm). The between-group difference (95% CI) was -17.6 (−32.5, −2.8). Day 5 mycological response was 78.9% (rezafungin arm) and 58.7% (caspofungin arm; difference [95% CI]: 19.3 [3.3, 35.2]; Figure 1). Conclusions Integrated analysis of pooled STRIVE/ReSTORE study data revealed similar incidence of drug-related TEAEs and SAEs in patients aged ≥65 years treated with rezafungin or caspofungin. Further analyses are required to understand underlying factors influencing between-group differences regarding treatment outcomes.

BACKGROUND:Rezafungin, a new US Food and Drug Administration-approved, long-acting echinocandin to treat candidaemia and invasive candidiasis, was efficacious with a similar safety profile to caspofungin in clinical trials. We conducted pooled analyses of the phase 2 STRIVE and phase 3 ReSTORE rezafungin trials. METHODS:ReSTORE was a multicentre, double-blind, double-dummy, randomised phase 3 trial conducted at 66 tertiary care centres in 15 countries. STRIVE was a multicentre, double-blind, double-dummy, randomised phase 2 trial conducted at 44 centres in 10 countries. Adults (≥18 years) with candidaemia or invasive candidiasis were treated with once-a-week intravenous rezafungin (400 mg and 200 mg) or once-a-day intravenous caspofungin (70 mg and 50 mg). Efficacy was evaluated in a pooled modified intent-to-treat (mITT) population. Primary efficacy endpoint was day 30 all-cause mortality (tested for non-inferiority with a pre-specified margin of 20%). Secondary efficacy endpoint was mycological response. Safety was also evaluated. The STRIVE and ReSTORE trials are registered with ClinicalTrials.gov, NCT02734862 and NCT03667690, and both studies are complete. FINDINGS:ReSTORE was conducted from Oct 12, 2018, to Oct 11, 2021, and STRIVE from July 26, 2016, to April 18, 2019. The mITT population, pooling the data from the two trials, comprised 139 patients for rezafungin and 155 patients for caspofungin. Day 30 all-cause mortality rates were comparable between groups (19% [26 of 139] for the rezafungin group and 19% [30 of 155] for the caspofungin group) and the upper bound of the 95% CI for the weighted treatment difference was below 10% (-1·5% [95% CI -10·7 to 7·7]). Mycological eradication occurred by day 5 in 102 (73%) of 139 rezafungin patients and 100 (65%) of 155 caspofungin patients (weighted treatment difference 10·0% [95% CI -0·3 to 20·4]). Safety profiles were similar across groups. INTERPRETATION:Rezafungin was non-inferior to caspofungin for all-cause mortality, with a potential early treatment benefit, possibly reflecting rezafungin's front-loaded dosing regimen. These findings are of clinical importance in fighting active and aggressive infections and reducing the morbidity and mortality caused by candidaemia and invasive candidiasis. FUNDING:Melinta Therapeutics and Cidara Therapeutics.

Importance A safe and effective treatment for recurrent Clostridioides difficile infection (CDI) is urgently needed. Antibiotics kill toxin-producing bacteria but do not repair the disrupted microbiome, which promotes spore germination and infection recurrence. Objectives To evaluate the safety and rate of CDI recurrence after administration of investigational microbiome therapeutic SER-109 through 24 weeks. Design, Setting, and Participants This phase 3, single-arm, open-label trial (ECOSPOR IV) was conducted at 72 US and Canadian outpatient sites from October 2017 to April 2022. Adults aged 18 years or older with recurrent CDI were enrolled in 2 cohorts: (1) rollover patients from the ECOSPOR III trial who had CDI recurrence diagnosed by toxin enzyme immunoassay (EIA) and (2) patients with at least 1 CDI recurrence (diagnosed by polymerase chain reaction [PCR] or toxin EIA), inclusive of their acute infection at study entry. Interventions SER-109 given orally as 4 capsules daily for 3 days following symptom resolution after antibiotic treatment for CDI. Main Outcomes and Measures The main outcomes were safety, measured as the rate of treatment-emergent adverse events (TEAEs) in all patients receiving any amount of SER-109, and cumulative rates of recurrent CDI (toxin-positive diarrhea requiring treatment) through week 24 in the intent-to-treat population. Results Of 351 patients screened, 263 were enrolled (180 [68.4%] female; mean [SD] age, 64.0 [15.7] years); 29 were in cohort 1 and 234 in cohort 2. Seventy-seven patients (29.3%) were enrolled with their first CDI recurrence. Overall, 141 patients (53.6%) had TEAEs, which were mostly mild to moderate and gastrointestinal. There were 8 deaths (3.0%) and 33 patients (12.5%) with serious TEAEs; none were considered treatment related by the investigators. Overall, 23 patients (8.7%; 95% CI, 5.6%-12.8%) had recurrent CDI at week 8 (4 of 29 [13.8%; 95% CI, 3.9%-31.7%] in cohort 1 and 19 of 234 [8.1%; 95% CI, 5.0%-12.4%] in cohort 2), and recurrent CDI rates remained low through 24 weeks (36 patients [13.7%; 95% CI, 9.8%-18.4%]). At week 8, recurrent CDI rates in patients with a first recurrence were similarly low (5 of 77 [6.5%; 95% CI, 2.1%-14.5%]) as in patients with 2 or more recurrences (18 of 186 [9.7%; 95% CI, 5.8%-14.9%]). Analyses by select baseline characteristics showed consistently low recurrent CDI rates in patients younger than 65 years vs 65 years or older (5 of 126 [4.0%; 95% CI, 1.3%-9.0%] vs 18 of 137 [13.1%; 95% CI, 8.0%-20.0%]) and patients enrolled based on positive PCR results (3 of 69 [4.3%; 95% CI, 0.9%-12.2%]) vs those with positive toxin EIA results (20 of 192 [10.4%; 95% CI, 6.5%-15.6%]). Conclusions and Relevance In this trial, oral SER-109 was well tolerated in a patient population with recurrent CDI and prevalent comorbidities. The rate of recurrent CDI was low regardless of the number of prior recurrences, demographics, or diagnostic approach, supporting the beneficial impact of SER-109 for patients with CDI. Trial Registration ClinicalTrials.gov identifier: NCT03183141

Abstract Background Rezafungin is a next-generation echinocandin in development for treatment of candidaemia and invasive candidiasis (IC) and for prevention of invasive fungal disease caused by Candida, Aspergillus and Pneumocystis spp. in blood and marrow transplantation. Rezafungin once-weekly (QWk) was compared to caspofungin once-daily (QD) in two double-blind, randomized, controlled trials in patients with candidaemia and/or IC: STRIVE (Phase 2; NCT02734862) and the recently completed ReSTORE (Phase 3; NCT03667690). STRIVE demonstrated the efficacy and safety profile of rezafungin. ReSTORE showed rezafungin noninferiority to caspofungin for 30 day all-cause mortality (ACM) and global response at Day 14 with comparable safety. Patient-level meta-analyses of efficacy and safety from both trials are presented. Methods Details of STRIVE and ReSTORE were previously described. In this analysis of data from both trials, patients who received rezafungin QWk (400 mg in Week 1, then 200 mg) were compared with those who received caspofungin QD (70 mg on Day 1 followed by 50 mg) for ≥14 days (up to 4 weeks). Efficacy endpoints included 30 day ACM (primary US FDA), mycological response at Day 5 (secondary), and time to first negative blood culture (TTNBC) (exploratory). Safety was evaluated by adverse events (AEs). Results Groups were well matched (Table 1). Figure 1 shows 30 day ACM (overall and by final diagnosis). Mycological response at Day 5 was 73.4% (102/139) and 64.5% (100/155) in rezafungin and caspofungin groups, respectively (difference=9.5, 95% CI=−0.9, 19.9). In patients with positive blood culture before randomization, median TTNBC was 22.3 h in rezafungin-treated versus 26.3 h in caspofungin-treated patients (stratified log rank p=0.0034, not adjusted for multiplicity). The summary of AEs (Table 2) demonstrates similar outcomes for rezafungin and caspofungin groups. Conclusions In the Phase 2/3 patient-level meta-analysis, rezafungin QWk demonstrated efficacy with a similar 30 day ACM rate and safety comparable to that of caspofungin QD. Data for mycological eradication at Day 5 and TTNBC support results from the primary efficacy endpoint and provide initial evidence for the theory that high, front-loaded drug exposure leads to faster fungal clearance. Further analysis of this integrated dataset may provide additional insights on rezafungin efficacy and safety.Table 1. Baseline demographics/characteristics in the patient-level meta-analysis of STRIVE and ReSTORE (mITT populationa) Demographic or characteristic Rezafungin 400 mg/200 mg weekly (N=139) Caspofungin 70 mg/50 mg daily (N=155) Age, years, mean ± SD (range) 59.8 ± 15.7 (19, 91) 60.8 ± 15.0 (20, 93) Age <65 years, n (%) 82 (59.0) 92 (59.4) Age ≥65 years, n (%) 57 (41.0) 63 (40.6) Female, n (%) 49 (35.3) 65 (41.9) Race, n (%) ȃAsian 24 (17.3) 34 (21.9) ȃBlack or African American 11 (7.9) 8 (5.2) ȃWhite 95 (68.3) 106 (68.4) ȃOther/not reported 9 (6.5) 7 (4.5) Final diagnosis, n (%) ȃCandidaemia 100 (71.9) 115 (74.2) ȃInvasive candidiasisb 39 (28.1) 40 (25.8) Modified APACHE II score, n (%)c ȃ≥20 21 (15.1) 26 (16.8) ȃ<20 116 (83.5) 126 (81.3) mITT, modified ITT. mITT population: patients with positive cultures from blood or another normally sterile site ≤96 h before randomization. IC group includes some subjects with deep tissue infection and candidaemia. Reported for patients with APACHE II score data available.Figure 1. Primary and secondary efficacy endpoints in the patient-level meta-analysis of STRIVE and ReSTORE: overall and by final diagnosis (mITT population). Data could not be combined for the primary endpoints of global cure at Day 14 (ReSTORE) and overall cure at Day 14 (STRIVE) due to differences in the definitions and methods of each study. (a) 30 day ACM. (b) Mycological eradication on Day 5.Table 2. Summary of TEAE data from the patient-level meta-analysis of STRIVE and ReSTORE (safety population) Parameter Number of subjects (%) Rezafungin 400 mg/200 mg weekly (N=151) Caspofungin 70 mg/50 mg daily (N=166) ≥1 TEAE 138 (91.4) 138 (83.1) Study drug-related TEAE 22 (14.6) 18 (10.8) Serious TEAE 83 (55.0) 81 (48.8) TEAE leading to study drug discontinuation 14 (9.3) 15 (9.0) TEAE, treatment-emergent adverse event.

Background Rezafungin is a next-generation, once-a-week echinocandin in development for the treatment of candidaemia and invasive candidiasis and for the prevention of invasive fungal disease caused by Candida, Aspergillus, and Pneumocystis spp after blood and marrow transplantation. We aimed to compare the efficacy and safety of intravenous rezafungin versus intravenous caspofungin in patients with candidaemia and invasive candidiasis. Methods ReSTORE was a multicentre, double-blind, double-dummy, randomised phase 3 trial done at 66 tertiary care centres in 15 countries. Adults (>= 18 years) with systemic signs and mycological confirmation of candidaemia or invasive candidiasis were eligible for inclusion and randomly assigned (1:1) to receive intravenous rezafungin once a week (400 mg in week 1, followed by 200 mg weekly, for a total of two to four doses) or intravenous caspofungin (70 mg loading dose on day 1, followed by 50 mg daily) for no more than 4 weeks. The primary endpoints were global cure (consisting of clinical cure, radiological cure, and mycological eradication) at day 14 for the European Medical Agency (EMA) and 30-day all-cause mortality for the US Food and Drug Administration (FDA), both with a target non-inferiority margin of 20%, assessed in the modified intention-to-treat population (all patients who received one or more doses of study drug and had documented Candida infection based on a culture from blood or another normally sterile site obtained within 96 h before randomisation). Safety was evaluated by the incidence and type of adverse events and deaths in the safety population, defined as all patients who received any amount of study drug. The trial is registered with ClinicalTrials.gov, NCT03667690, and is complete. Findings Between Oct 12, 2018, and Aug 29, 2021, 222 patients were screened for inclusion, and 199 patients (118 [59%] men; 81 [41%] women; mean age 61 years [SD 15middot2]) were randomly assigned (100 [50%] patients to the rezafungin group and 99 [50%] patients to the caspofungin group). 55 (59%) of 93 patients in the rezafungin group and 57 (61%) of 94 patients in the caspofungin group had a global cure at day 14 (weighted treatment difference -1middot1% [95% CI - 14middot9 to 12middot7]; EMA primary endpoint). 22 (24%) of 93 patients in the rezafungin group and 20 (21%) of 94 patients in the caspofungin group died or had an unknown survival status at day 30 (treatment difference 2middot4% [95% CI - 9middot7 to 14middot4]; FDA primary endpoint). In the safety analysis, 89 (91%) of 98 patients in the rezafungin group and 83 (85%) of 98 patients in the caspofungin group had at least one treatment-emergent adverse event. The most common treatment-emergent adverse events that occurred in at least 5% of patients in either group were pyrexia, hypokalaemia, pneumonia, septic shock, and anaemia. 55 (56%) patients in the rezafungin group and 52 (53%) patients in the caspofungin group had serious adverse events. Interpretation Our data show that rezafungin was non-inferior to caspofungin for the primary endpoints of day-14 global cure (EMA) and 30-day all-cause mortality (FDA). Efficacy in the initial days of treatment warrants evaluation. There were no concerning trends in treatment-emergent or serious adverse events. These phase 3 results show the efficacy and safety of rezafungin and support its ongoing development. Funding Cidara Therapeutics and Mundipharma. Copyright (c) 2022 Elsevier Ltd. All rights reserved.

Introduction: Recurrence of C. difficile infection (CDI) is due to the failure of antibiotics to eradicate spores that can germinate post-treatment. ADS024, an orally delivered single-strain live biotherapeutic product (Bacillus velezensis), kills C. difficile and degrades its toxins. This study (NCT04891965) evaluated the safety and efficacy of ADS024 for the prevention of CDI recurrence (rCDI). Methods: The phase 1b, randomized, placebo-controlled, double-blind, multicenter study enrolled patients cured after a course of standard-of-care antibiotics for a recent CDI episode. Patients received ADS024 (5x109 CFU/daily) or placebo (3:1) orally for 7 (Cohort A, n = 8) or 28 days (Cohort B, n = 28). Patients were followed for 6 months after last dose. The primary endpoint was safety/tolerability; key secondary endpoints included evaluation of recurrence, time to recurrence (TTR), change from baseline in C. difficile toxin levels, presence of ADS024, and microbiome analyses (shallow shotgun sequencing and C. difficile qPCR). Results: Of 36 enrolled patients, 17 had prior episodes (rCDI); 31 completed the study; 69% were female, median age was 58 years, and median (range) duration of exposure was 28 days (2-28). Adverse event data show ADS024 was well-tolerated (Table 1). Recurrence was observed in 4/27 patients (15%, 3/4 rCDI) treated with ADS024 (median TTR, 10 days [range, 2-14]) and 1 (11%) with placebo (TTR, 108 days). Increase in C. difficile counts and increase in toxin levels appeared temporally associated with recurrence. C. difficile toxin levels declined from baseline to end of dosing with ADS024 vs increased with placebo (Figure 1). A decreasing trend in C. difficile counts occurred during ADS024 exposure compared with placebo. ADS024 was detected in 7 patients and did not persist after end of dosing. No significant changes in alpha-diversity between treatment arms were detected. Significant differences in beta-diversity occurred over time and between treatment arms. R2 values showed overall beta-diversity variations by time and treatment were small vs other factors (eg, inter-patient variation). Conclusion: ADS024 appears safe and well-tolerated and CDI recurrence frequency was similar between arms in this small study. ADS024 did not engraft. Overall, low variance in alpha- and beta-diversity was observed. C. difficile toxin levels declined from baseline to Week 4 with ADS024 and increased with placebo. These findings warrant further investigation of ADS024. Table 1. - TEAEs and TRAEs (Safety Analysis Set). TEAE, Treatment-Emergent Adverse Event; TRAE, Treatment-Related Adverse Event Pooled ADS024 (n = 27) Placebo (n = 9) n (%) Treatment-Emergent Adverse Events Patients with ≥1 TEAE 17 (63) 6 (67) Mild 8 (30) 3 (33) Moderate 6 (22) 3 (33) Severe 3 (11) 0 Most common TEAEs (incidence ≥20% in ADS024 arm) Diarrhea 8 (30) 3 (33) Flatulence 7 (26) 2 (22) Abdominal pain 6 (22) 1 (11) Patients with ≥1 Serious TEAE 4 (15) 1 (11) C. difficile infection 2 (7) 0 Wound infection 1 (4) 0 Abdominal pain 1 (4) 0 Treatment-Related Adverse Events Patients with ≥1 TRAE 4 (15) 1 (11) Mild 4 (15) 1 (11) Moderate 0 0 Severe 0 0 Most common TRAEs (incidence ≥10% in ADS024 arm) Flatulence 3 (11) 1 (11) Abdominal pain 3 (11) 0 Patients with ≥1 Serious TRAE 0 0 Figure 1.: Change from baseline in C. difficile toxin levels. a Evaluated using the in vitro diagnostic enzyme immunoassay (tgcBiomics ELISA) for the detection of toxin A and toxin B produced by toxigenic strains of C. difficile in human feces. b No toxin data available for placebo patients in Cohort A; 1 patient had all toxin levels below limits of quantification and samples from the other patient were not tested early enough and went out of stability. BL, baseline; OD, optical density.

Abstract Background Although comorbidities are risk factors for recurrent Clostridioides difficile infection (rCDI), many clinical trials exclude patients with medical conditions such as malignancy or immunosuppression. In a phase 3, double-blind, placebo-controlled, randomized trial (ECOSPOR III), fecal microbiota spores, live (VOWST, Seres Therapeutics; hereafter “VOS,” formerly SER-109), an oral microbiota therapeutic, significantly reduced the risk of rCDI at week 8. We evaluated the efficacy of VOS compared with placebo in patients with comorbidities and other risk factors for rCDI. Methods Adults with rCDI were randomized to receive VOS or placebo (4 capsules daily for 3 days) following standard-of-care antibiotics. In this post hoc analysis, the rate of rCDI through week 8 was assessed in VOS-treated participants compared with placebo for subgroups including (i) Charlson comorbidity index (CCI) score category (0, 1–2, 3–4, ≥5); (ii) baseline creatinine clearance (<30, 30–50, >50 to 80, or >80 mL/minute); (iii) number of CDI episodes, inclusive of the qualifying episode (3 and ≥4); (iv) exposure to non-CDI-targeted antibiotics after dosing; and (v) acid-suppressing medication use at baseline. Results Of 281 participants screened, 182 were randomized (59.9% female; mean age, 65.5 years). Comorbidities were common with a mean overall baseline age-adjusted CCI score of 4.1 (4.1 in the VOS arm and 4.2 in the placebo arm). Across all subgroups analyzed, VOS-treated participants had a lower relative risk of recurrence compared with placebo. Conclusions In this post hoc analysis, VOS reduced the risk of rCDI compared with placebo, regardless of baseline characteristics, concomitant medications, or comorbidities.

Abstract Background Several demographic and clinical characteristics, including age, sex, medication use and presence of comorbid conditions are considered risk factors for recurrent CDI (rCDI). We examined the efficacy of an investigational purified oral microbiome therapeutic, SER-109, versus placebo in an exploratory analysis of subgroups of patients with risk factors for recurrence who enrolled in ECOSPOR III, a double-blind, placebo controlled trial. Forest Plot of Relative Risks for Recurrence at Week 8 for Selected Baseline Characteristics in the ITT population Methods Patients with ≥ 3 CDI episodes were treated with SER-109 or placebo (four capsules daily for three days) following standard treatment of CDI. The primary efficacy objective was to demonstrate superiority of SER-109 versus placebo in reducing rCDI up to 8 weeks after treatment. In this exploratory analysis, we analyzed the rate of CDI recurrence among SER-109 treated subjects compared to placebo in subgroups defined by rCDI baseline risk factors: proton-pump inhibitor use, number of CDI recurrences, prior FMT history, presence of comorbid conditions and exposure to non-CDI antibiotics after dosing. We also analyzed the rate of CDI recurrence among SER-109 treated subjects by age (≥ 65 and ≤ 65) and gender, which were pre-specified. Results Of 281 patients screened,182 were enrolled. Overall recurrence rates were lower in SER-109 treated patients compared to placebo (12.4% vs 39.8%, respectively); relative risk (RR), 0.32 [95% CI, 0.18-0.58; P< 0.001 for RR< 1.0:P< 0.001 for RR< 0.833]. Co-morbidities including diabetes, renal disease, malignancy, cardiac disease, COPD/asthma, colitis, or immunocompromised status were observed in most patients in the overall study population; 33.5%, 32.4% and 34.1% had 0, 1, or ≥ 2 comorbidities. SER-109 was consistently observed to show greater benefit than placebo in reducing CDI recurrence in all subgroups regardless of the presence or absence of the rCDI risk factor (Fig 1). Conclusion Regardless of risk factor status, SER-109 reduced recurrence of CDI compared to placebo. Most subjects in ECOSPOR III had co-morbidities consistent with the broad inclusion criteria in this Phase 3 trial. Despite a high proportion of patients with co-morbidities in ECOSPOR III, SER-109 significantly reduced the risk of recurrence compared to placebo. Disclosures Stuart H. Cohen, MD, Seres (Research Grant or Support) Thomas J. Louie, MD, Artugen (Advisor or Review Panel member)Crestone (Consultant, Grant/Research Support)Da Volterra (Advisor or Review Panel member)Finch Therapeutics (Grant/Research Support, Advisor or Review Panel member)MGB Biopharma (Grant/Research Support, Advisor or Review Panel member)Rebiotix (Consultant, Grant/Research Support)Seres Therapeutics (Consultant, Grant/Research Support)Summit PLC (Grant/Research Support)Vedanta (Grant/Research Support, Advisor or Review Panel member) Matthew Sims, MD, PhD, Astra Zeneca (Independent Contractor)Diasorin Molecular (Independent Contractor)Epigenomics Inc (Independent Contractor)Finch (Independent Contractor)Genentech (Independent Contractor)Janssen Pharmaceuticals NV (Independent Contractor)Kinevant Sciences gmBH (Independent Contractor)Leonard-Meron Biosciences (Independent Contractor)Merck and Co (Independent Contractor)OpGen (Independent Contractor)Prenosis (Independent Contractor)Regeneron Pharmaceuticals Inc (Independent Contractor)Seres Therapeutics Inc (Independent Contractor)Shire (Independent Contractor)Summit Therapeutics (Independent Contractor) Elaine E. Wang, MD, Seres Therapeutics (Employee) Elaine E. Wang, MD, Seres Therapeutics (Employee, Shareholder) Barbara McGovern, MD, Seres Therapeutics (Employee, Shareholder) Kelly Brady, MS, Seres Therapeutics (Employee, Shareholder) Lisa von Moltke, MD, Seres Therapeutics (Employee, Shareholder)

Introduction: Disruption of the microbiome is key to the pathogenesis of recurrent Clostridioides difficile infection (CDI). CP101 is an investigational orally administered microbiome therapeutic designed to restore microbiome diversity and enable early intervention in the management of recurrent CDI. Engraftment, the presence of administered microbes that colonize the gastrointestinal tract, is a key pharmacokinetic marker of microbiome therapeutics; however, there is a paucity of data on the impact of engraftment on clinical efficacy in recurrent CDI. Methods: We conducted a double-blind, randomized, placebo-controlled trial (PRISM3) enrolling adults who received standard-of-care antibiotics for recurrent CDI. Patients with first CDI recurrence at high-risk for further recurrence (≥65 years), or those with two or more recurrences were eligible. The qualifying CDI episode was diagnosed prior to study entry by guideline recommended testing (PCR-based or toxin EIA-based). Following CDI antibiotics, participants completed a minimum 2-day washout period to limit the impact of residual antibiotics on CP101. Eligible participants were randomized 1:1 to receive one-time oral administration of CP101 or placebo without bowel preparation. The primary efficacy endpoint was sustained clinical cure, defined as an absence of CDI recurrence through Week 8 following dosing. Engraftment of CP101 was measured using 16S rRNA gene amplicon sequencing. Results: Among the 198 enrolled participants analyzed, the CP101 arm demonstrated a statistically significant and clinically meaningful improvement in sustained clinical cure compared to placebo through Week 8 (74.5% [76/102] vs 61.5% [59/96], P=0.0488). Participants treated with CP101 had significantly higher engraftment of CP101-associated taxa compared to placebo (Fig. 1a), and engraftment was both rapid and sustained over time (p< 0.0001 at Week 1, p< 0.0001 at Week 8). Clinically, CP101 engraftment was strongly associated with efficacy in recurrent CDI. Among participants with successful engraftment at Week 1 following CP101, 96.0% achieved a sustained clinical cure, while unsuccessful engraftment resulted in a 54.2% sustained clinical cure rate, similar to placebo following CDI antibiotics (p< 0.001) (Fig. 1b-c). Conclusion: These data suggest that successful CP101 engraftment drives high rates of sustained clinical cure in recurrent CDI. Future trials will deploy strategies to optimize engraftment by further minimizing the effect of residual CDI antibiotics.Figure 1.: a. CP101 showed significant engraftment in PRISM3. b. CP101 engraftment showed a bimodal distribution in PRISM3. c. CP101 engraftment strongly associated with sustained clinical cure in PRISM3.

BACKGROUND:The safety and efficacy of the AZD1222 (ChAdOx1 nCoV-19) vaccine in a large, diverse population at increased risk for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in the United States, Chile, and Peru has not been known. METHODS:In this ongoing, double-blind, randomized, placebo-controlled, phase 3 clinical trial, we investigated the safety, vaccine efficacy, and immunogenicity of two doses of AZD1222 as compared with placebo in preventing the onset of symptomatic and severe coronavirus disease 2019 (Covid-19) 15 days or more after the second dose in adults, including older adults, in the United States, Chile, and Peru. RESULTS:A total of 32,451 participants underwent randomization, in a 2:1 ratio, to receive AZD1222 (21,635 participants) or placebo (10,816 participants). AZD1222 was safe, with low incidences of serious and medically attended adverse events and adverse events of special interest; the incidences were similar to those observed in the placebo group. Solicited local and systemic reactions were generally mild or moderate in both groups. Overall estimated vaccine efficacy was 74.0% (95% confidence interval [CI], 65.3 to 80.5; P<0.001) and estimated vaccine efficacy was 83.5% (95% CI, 54.2 to 94.1) in participants 65 years of age or older. High vaccine efficacy was consistent across a range of demographic subgroups. In the fully vaccinated analysis subgroup, no severe or critical symptomatic Covid-19 cases were observed among the 17,662 participants in the AZD1222 group; 8 cases were noted among the 8550 participants in the placebo group (<0.1%). The estimated vaccine efficacy for preventing SARS-CoV-2 infection (nucleocapsid antibody seroconversion) was 64.3% (95% CI, 56.1 to 71.0; P<0.001). SARS-CoV-2 spike protein binding and neutralizing antibodies increased after the first dose and increased further when measured 28 days after the second dose. CONCLUSIONS:AZD1222 was safe and efficacious in preventing symptomatic and severe Covid-19 across diverse populations that included older adults. (Funded by AstraZeneca and others; ClinicalTrials.gov number, NCT04516746.).

Introduction: Microbiome diversity is a surrogate marker for microbiome health with decreased diversity observed in many diseases. Key to disease pathogenesis in recurrent Clostridioides difficile infection (CDI) is decreased microbiome diversity and impaired colonization resistance. CP101 is an investigational orally administered microbiome therapeutic designed to restore microbiome diversity and enable early intervention in the management of recurrent CDI. Microbiome diversity is a key pharmacodynamic marker in recurrent CDI; however, data on the impact of increasing diversity on efficacy is scarce. Methods: We conducted a double-blind, randomized, placebo-controlled trial (PRISM3) enrolling adults who received standard-of-care antibiotics for recurrent CDI. Patients with first CDI recurrence at high-risk for further recurrence (≥65 years), or those with two or more recurrences were eligible. The qualifying CDI episode was diagnosed prior to study entry by guideline recommended testing (PCR-based or toxin EIA-based). Following CDI antibiotics, participants completed a minimum 2-day washout period. Eligible participants were randomized 1:1 to receive one-time oral administration of CP101 or placebo without bowel preparation. The primary efficacy endpoint was sustained clinical cure, defined as an absence of CDI recurrence through Week 8 following dosing. Diversity of the intestinal microbiome was measured at baseline, Week 1, and Week 8 using 16S rRNA gene amplicon sequencing. Results: Among the 198 enrolled participants analyzed, the CP101 arm demonstrated a statistically significant and clinically meaningful improvement in sustained clinical cure compared to placebo through Week 8 (74.5% [76/102] vs 61.5% [59/96], P=0.0488). Alpha diversity was low in the CP101 and placebo arms at baseline, and similar between both groups. Participants treated with CP101 achieved significantly higher alpha diversity compared to placebo, and the increase in diversity was rapid and sustained over time (p< 0.001 at Week 1, p< 0.0001 at Week 8) (Fig. 1a). Participants who received CP101 also had a significantly greater change in their microbial community composition from baseline compared to placebo at Week 1 (p< 0.001). Clinically, an increase in microbiome diversity at Week 1 was associated with sustained clinical cure through Week 8 (p< 0.001) (Fig. 1b). Conclusion: These data suggest that CP101 restores microbiome diversity, leading to colonization resistance and driving sustained clinical cure in recurrent CDI.Figure 1.: a. CP101 drives restoration of microbiome diversity. B. An increase in microbiome diversity at Week 1 is associated with sustained clinical cure through Week 8.

Introduction: Disruption of the microbiome is key to pathogenesis of recurrent Clostridioides difficile infection (CDI). Placebo-controlled trials assessing microbiome therapeutics have demonstrated efficacy in recurrent CDI; however, there is a paucity of data on response durability and long-term safety. CP101 is an investigational orally administered microbiome therapeutic designed to restore microbiome diversity and enable early intervention in the management of recurrent CDI. Given its complete consortia composition, CP101 is hypothesized to have a durable effect. Methods: We conducted a double-blind, randomized, placebo-controlled trial (PRISM3) enrolling adults who received standard-of-care antibiotics for recurrent CDI. Patients with first CDI recurrence at high-risk for further recurrence (≥65 years), or those with two or more recurrences were eligible. The qualifying CDI episode was diagnosed prior to study entry by guideline recommended testing (PCR-based or toxin EIA-based). Following CDI antibiotics, eligible participants were randomized 1:1 to receive one-time oral administration of CP101 or placebo without bowel preparation. The primary efficacy endpoint was sustained clinical cure, defined as an absence of CDI recurrence through Week 8 following dosing. Secondary endpoints of efficacy and safety were evaluated through Week 24. Results: 198 enrolled participants were analyzed with 28.8% of participants having one CDI recurrence prior to study entry and 61.1% of the qualifying CDI episodes diagnosed by PCR-based testing. Baseline characteristics were similar between CP101 (n=102) and placebo (n=96) arms. As previously reported, the CP101 arm demonstrated a statistically significant and clinically meaningful improvement in sustained clinical cure compared to the placebo arm through Week 8. On long-term assessment, CP101 demonstrated clinically meaningful durability and the proportion of participants with sustained clinical cure through Week 24 remained significantly higher in the CP101 arm compared to placebo (73.5% [75/102] vs 59.4% [57/96], P=0.0347) (Fig. 1a). Time-to-event analysis through Week 24 showed a statistically significant and durable benefit, favoring CP101 compared to placebo (P=0.018) (Fig. 1b). Through Week 24, adverse events were similar across both arms, and no treatment-related SAEs were reported with CP101. Conclusion: On long-term assessment, CP101 demonstrated durable efficacy for the prevention of recurrent CDI and a safety profile similar to placebo through Week 24.Figure 1.: a. CP101 demonstrated durable efficacy for the prevention of recurrent CDI in PRISM3. b. CP101 demonstrated a durable effect over time compared to placebo in PRISM3.