Multicenter, Double-Blind, Randomized, Phase 2 Study Evaluating the Novel Antibiotic Cadazolid in Patients with Clostridium difficile Infection.

Cadazolid, a novel fluoroquinolone-oxazolidinone antibiotic, exhibits potent in vitro activity against Clostridium difficile, including the epidemic BI/NAP1/027 strain. This multicenter, randomized, double-blind, active reference group, phase 2 study evaluated the efficacy and safety of oral cadazolid in treatment of adult patients with C. difficile infection (CDI). Eligible patients with first occurrence/first recurrence of CDI were randomized 1:1:1:1 to 250, 500, or 1,000 mg cadazolid twice daily (BID) or oral 125 mg vancomycin four times daily (QID) for 10 days. The primary endpoint was clinical cure at test of cure (48 ± 24 h after the end of treatment; modified intent-to-treat population), defined as resolution of diarrhea with no further CDI treatment required. Secondary endpoints included recurrence rate, sustained clinical response (clinical cure without recurrence), and time to diarrhea resolution. Of 84 patients enrolled, 20, 22, 20, and 22 received 250, 500, or 1,000 mg cadazolid BID or 125 mg vancomycin QID, respectively. The primary endpoint was achieved in 76.5% (80% confidence interval [CI], 58.4, 89.3), 80.0% (63.9, 91.0), 68.4% (51.1, 82.5), and 68.2% (52.3, 81.3) of patients, respectively. There was no evidence of a cadazolid dosage-dependent response. Each dosage of cadazolid resulted in a lower recurrence rate than with vancomycin (18.2 to 25.0% versus 50%). Consequently, higher sustained clinical response rates were observed with cadazolid (46.7 to 60.0%) than with vancomycin (33.3%). The times to diarrhea resolution were similar for cadazolid and vancomycin. Cadazolid was well tolerated, with no safety signal observed. The results of this phase 2 study support further clinical development of cadazolid. (This study has been registered in the United States at ClinicalTrials.gov under registration no. NCT01222702 and in Europe with the European Medicines Agency under registration no. EUDRA-CT 2010-020941-29.).

Comparative Efficacy of Relapsing Multiple Sclerosis Therapies: Model-Based Meta-Analyses for Confirmed Disability Accumulation and Annualized Relapse Rate.

BACKGROUND: Multiple sclerosis (MS) is an inflammatory autoimmune disorder and the most common cause of non-traumatic disability in young adults. The Phase 3 OPTIMUM study evaluated the efficacy and safety of oral ponesimod, a selective sphingosine-1-phosphate (S1P) receptor 1 modulator, vs. teriflunomide in patients with relapsing multiple sclerosis (RMS). The aim of this analysis was to assess the effect of ponesimod and other disease modifying treatments (DMTs) compared to placebo, as measured by 12-week confirmed disability accumulation (CDA) and annualized relapse rate (ARR) in RMS patients. METHODS: A database was developed by Certara Inc. (USA) based on relevant clinical trials identified from searching the following sources: PubMed, clinicaltrials.gov, FDA and EMEA documents, and conference abstracts. This database consisted of 203 unique randomized controlled trials (RCTs) with 74 MS treatments and was subsequently filtered to include RCTs with more than 25 patients receiving monotherapy to treat RMS for at least 48 weeks. A model-based meta-analysis (MBMA) was performed on the filtered database to assess treatment effects measured by CDA and ARR. Analyzed data for CDA were digitized from published Kaplan-Meier plots. A Weibull distribution was assumed to adequately capture the relationship of CDA probability over time, and hazard ratios (HRs) between treatments were assumed constant over time (proportional hazards). HRs were estimated for 12-week CDA for 17 DMTs vs. placebo. Additionally, mean ARR for each treatment arm was modelled, where relative effect versus placebo was estimated as a fixed effect parameter for each unique drug. A dose-response relationship was included if data for multiple doses were available. Relative treatment effect covariates explored for CDA and ARR included: percent of patients with relapsing-remitting MS (RRMS), trial start year, mean duration of disease, percent of patients who received DMTs within the prior 2 years (pDMT), mean number of relapses in the prior year, mean age, mean baseline EDSS score, and mean treatment duration (for ARR). RESULTS: The 12-week CDA model utilized longitudinal data from 26 RCTs (18 unique treatments [including placebo]), 69 treatment arms, 31,160 patients). The ARR model utilized data from 40 RCTs (18 unique treatments [including placebo], 100 treatment arms, 33,686 patients). Compared to placebo, ponesimod significantly reduced 12-week CDA by 39% (HR: 0.61; 95% CI: 0.45-0.82) and reduced ARR by 53% (rate ratio [RR]: 0.47; 95% CI: 0.39-0.58). Except for three DMTs (interferon ß-1b, glatiramer acetate, ozanimod), HR of 12-week CDA vs. placebo was significantly lower for the DMTs included in this analysis (HR range: 0.41 to 0.79). The ARR was significantly reduced for all DMTs compared to placebo (RR range: 0.29 to 0.82). A dose-response relationship indicated a potential dose-dependent effect (12-week CDA: 6 treatments; ARR: 8 treatments). Relative treatment effect was found to be significantly smaller in trials including more patients with prior DMT usage. Cross-trial heterogeneity in relative effects was assessed and found to be negligible; however, there is a possibility that confounders remain which may impact estimated relative treatment effects. CONCLUSIONS: Compared to placebo, ponesimod 20 mg significantly reduced both the risk of 12-week CDA and mean ARR, suggesting it has robust efficacy in the treatment of RMS. The study was funded by Janssen Research & Development, LLC.

An exposure-response analysis of ponesimod clinical efficacy in a randomized phase III study in patients with relapsing multiple sclerosis.

The efficacy of ponesimod and teriflunomide for the treatment of relapsing multiple sclerosis (MS) was compared in a randomized phase III trial. This study explores the exposure-response (E-R) relationships of efficacy end points (annualized relapse rate [ARR] and combined unique active lesions [CUALs]) of ponesimod observed in this trial. The E-R relationships were described using nonlinear mixed effects models for count data. The effect of baseline covariates (demography and prognostic factors) was also explored. Ponesimod 20 mg reduced ARR (primary end point) by 30.5% (95% confidence interval [CI]: 9.8% to 46.4%) and the number of CUALs by 56% (95% CI: 46% to 64%) between baseline and week 108 compared to teriflunomide 14 mg. The E-R analyses indicated a significant relationship between ARR and CUAL. In turn, CUAL was significantly related to ponesimod systemic exposure. Based on these relationships, the predicted reduction of ARR was relatively flat in the range of ponesimod systemic exposure achieved with the 20 mg clinical dose: the expected ARR decrease ranged from 28% (95% CI: 11% to 42%) at the 5th percentile of ponesimod exposure to 34% (95% CI: 19% to 47%) at the 95th percentile. No significant baseline covariates affected the ponesimod effects and, consequently, dosage adjustments are not warranted by these analyses. Although significant relationships were found between ARR and CUAL and between ponesimod exposure and CUAL, these analyses were supportive of the use of a flat 20 mg maintenance dose for ponesimod in adult patients with MS.

Ponesimod Compared With Teriflunomide in Patients With Relapsing Multiple Sclerosis in the Active-Comparator Phase 3 OPTIMUM Study: A Randomized Clinical Trial.

Importance: To our knowledge, the Oral Ponesimod Versus Teriflunomide In Relapsing Multiple Sclerosis (OPTIMUM) trial is the first phase 3 study comparing 2 oral disease-modifying therapies for relapsing multiple sclerosis (RMS). Objective: To compare the efficacy of ponesimod, a selective sphingosine-1-phosphate receptor 1 (S1P1) modulator with teriflunomide, a pyrimidine synthesis inhibitor, approved for the treatment of patients with RMS. Design, Setting, and Participants: This multicenter, double-blind, active-comparator, superiority randomized clinical trial enrolled patients from April 27, 2015, to May 16, 2019, who were aged 18 to 55 years and had been diagnosed with multiple sclerosis per 2010 McDonald criteria, with a relapsing course from the onset, Expanded Disability Status Scale (EDSS) scores of 0 to 5.5, and recent clinical or magnetic resonance imaging disease activity. Interventions: Patients were randomized (1:1) to 20 mg of ponesimod or 14 mg of teriflunomide once daily and the placebo for 108 weeks, with a 14-day gradual up-titration of ponesimod starting at 2 mg to mitigate first-dose cardiac effects of S1P1 modulators and a follow-up period of 30 days. Main Outcomes and Measures: The primary end point was the annualized relapse rate. The secondary end points were the changes in symptom domain of Fatigue Symptom and Impact Questionnaire-Relapsing Multiple Sclerosis (FSIQ-RMS) at week 108, the number of combined unique active lesions per year on magnetic resonance imaging, and time to 12-week and 24-week confirmed disability accumulation. Safety and tolerability were assessed. Exploratory end points included the percentage change in brain volume and no evidence of disease activity (NEDA-3 and NEDA-4) status. Results: For 1133 patients (567 receiving ponesimod and 566 receiving teriflunomide; median [range], 37.0 [18-55] years; 735 women [64.9%]), the relative rate reduction for ponesimod vs teriflunomide in the annualized relapse rate was 30.5% (0.202 vs 0.290; P < .001); the mean difference in FSIQ-RMS, -3.57 (-0.01 vs 3.56; P < .001); the relative risk reduction in combined unique active lesions per year, 56% (1.405 vs 3.164; P < .001); and the reduction in time to 12-week and 24-week confirmed disability accumulation risk estimates, 17% (10.1% vs 12.4%; P = .29) and 16% (8.1% vs 9.9; P = .37), respectively. Brain volume loss at week 108 was lower by 0.34% (-0.91% vs -1.25%; P < .001); the odds ratio for NEDA-3 achievement was 1.70 (25.0% vs 16.4%; P < .001). Incidence of treatment-emergent adverse events (502 of 565 [88.8%] vs 499 of 566 [88.2%]) and serious treatment-emergent adverse events (49 [8.7%] vs 46 [8.1%]) was similar for both groups. Treatment discontinuations because of adverse events was more common in the ponesimod group (49 of 565 [8.7%] vs 34 of 566 [6.0%]). Conclusions and Relevance: In this study, ponesimod was superior to teriflunomide on annualized relapse rate reduction, fatigue, magnetic resonance imaging activity, brain volume loss, and no evidence of disease activity status, but not confirmed disability accumulation. The safety profile was in line with the previous safety observations with ponesimod and the known profile of other S1P receptor modulators. Trial Registration: ClinicalTrials.gov Identifier: NCT02425644.

Cadazolid for the treatment of Clostridium difficile infection: results of two double-blind, placebo-controlled, non-inferiority, randomised phase 3 trials.

BACKGROUND: Cadazolid is a novel quinoxolidinone antibiotic developed for treating Clostridium difficile infection. We aimed to investigate the safety and efficacy of cadazolid compared with vancomycin in patients with C difficile infection. METHODS: IMPACT 1 and IMPACT 2 were identically designed, multicentre, double-blind, placebo-controlled, non-inferiority, randomised phase 3 trials. IMPACT 1 was done in Australia, Brazil, Canada, France, Germany, Italy, the Netherlands, Peru, Poland, Romania, Spain, and the USA, and IMPACT 2 was done in Argentina, Belgium, Brazil, Canada, Chile, Croatia, Czech Republic, Greece, Hungary, Israel, Romania, Slovakia, South Korea, the UK, and the USA. Patients (aged 18 years or older) with mild-to-moderate or severe C difficile infection (diarrhoea with positive glutamate dehydrogenase and toxin A or B enzyme immunoassays) were randomly assigned (1:1) with a randomisation list stratified by centre and C difficile infection episode type (block size of four), and allocation was masked to investigators and participants. Patients received either oral cadazolid 250 mg twice daily with vancomycin-matching placebo capsule four times daily or oral vancomycin 125 mg four times a day with cadazolid-matching placebo suspension twice daily for 10 days, with 30 days of follow-up. The primary efficacy outcome was non-inferiority (margin -10%) of cadazolid versus vancomycin for clinical cure in the modified intention-to-treat and per-protocol populations. Clinical cure was defined as resolution of diarrhoea with no additional treatment for C difficile infection. These trials are registered with ClinicalTrials.gov, numbers NCT01987895 (IMPACT 1) and NCT01983683 (IMPACT 2). FINDINGS: Between March 28, 2014, and March 24, 2017, for IMPACT 1, and Dec 13, 2013, and May 2, 2017, for IMPACT 2, 1263 participants were randomly assigned to receive cadazolid (306 in IMPACT 1 and 298 in IMPACT 2) or vancomycin (326 in IMPACT 1 and 311 in IMPACT 2). In the modified intention-to-treat population in IMPACT 1, 253 (84%) of 302 had clinical cure in the cadazolid group versus 271 (85%) of 318 in the vancomycin group. In IMPACT 2, 235 (81%) of 290 versus 258 (86%) of 301 had clinical cure. In the per-protocol population, 247 (88%) of 282 versus 264 (92%) of 288 had clinical cure in IMPACT 1 and 214 (87%) of 247 versus 237 (92%) of 259 in IMPACT 2. Non-inferiority for clinical cure to vancomycin was shown in IMPACT 1 but not in IMPACT 2 (IMPACT 1 treatment difference: -1·4 [95% CI -7·2 to 4·3] for modified intention to treat and -4·1 [-9·2 to 1·0] for per protocol; IMPACT 2: -4·7 [-10·7 to 1·3] for modified intention to treat and -4·9 [-10·4 to 0·6] for per protocol). The safety and tolerability profiles of the two antibiotics were similar. INTERPRETATION: Cadazolid was safe and well tolerated but did not achieve its primary endpoint of non-inferiority to vancomycin for clinical cure in one of two phase 3 C difficile infection trials. Therefore, further commercial development of cadazolid for C difficile infection is unlikely. FUNDING: Actelion Pharmaceuticals.