ABX464 (obefazimod) for moderate-to-severe, active ulcerative colitis: a phase 2b, double-blind, randomised, placebo-controlled induction trial and 48 week, open-label extension.

BACKGROUND: ABX464 (obefazimod) is a small molecule that selectively upregulates miR-124 in immune cells. We aimed to assess ABX464 as a treatment for patients with moderate-to-severe, active ulcerative colitis. METHODS: In this phase 2b, double-blind, randomised, placebo-controlled induction trial, patients were recruited from 95 centres (hospitals and health-care centres) in 16 countries. Eligible patients were aged 18-75 years, with a diagnosis of moderate-to-severe, active ulcerative colitis and a modified Mayo Score (MMS) of 5 points or higher, and a documented non-response or intolerance to previous treatment. Enrolled patients were randomly assigned (1:1:1:1) via an interactive voice and web response system to receive once daily oral ABX464 100 mg, ABX464 50 mg, ABX464 25 mg, or matched placebo. Randomisation was stratified according to study site (US vs non-US) and to whether the patient had previous exposure to second-line treatment with biologics or JAK inhibitors. The primary endpoint was the change from baseline in MMS at week 8. The primary efficacy analysis was done in the full analysis set (FAS), defined as all randomly assigned patients who received at least one dose of study treatment and had baseline data for at least one efficacy variable, and was analysed according to the principles of intention-to-treat. Safety analyses included patients who had been randomly assigned and who received at least one dose of study treatment. The 96 week open-label extension is ongoing. This study is registered with ClinicalTrials.gov, NCT04023396. FINDINGS: Between Aug 13, 2019, and April 16, 2021, 254 patients were randomly allocated to ABX464 100 mg (n=64), ABX464 50 mg (n=63), ABX464 25 mg (n=63), or placebo (n=64). Two patients, both in the ABX464 25 mg group, were excluded from the FAS. In the FAS at week 8, the least squares mean (LSM) change from baseline in MMS was -2·9 (95% CI -3·4 to -2·5) for the ABX464 100 mg group, -3·2 (-3·7 to -2·7) for the ABX464 50 mg group, -3·1 (-3·6 to -2·6) for the ABX464 25 mg group, and -1·9 (-2·4 to -1·5) for placebo group; the magnitude of the difference in MMS from baseline was significantly greater in all three ABX464 groups compared with placebo (p=0·0039 for ABX464 100 mg vs placebo, p=0·0003 for ABX464 50 mg vs placebo, and p=0·0010 for ABX464 25 mg vs placebo). The most frequently reported adverse event was headache, which was reported for 27 (42%) of 64 patients in the ABX464 100 mg group, 19 (30%) of 63 in the 50 mg group, 13 (21%) of 62 in the 25 mg group, and five (8%) of 64 in the placebo group. Severe (grade 3) headache was reported for three (5%) patients in the ABX464 group 100 mg group, two (3%) in the ABX464 50 mg group, one (2%) in the ABX464 25 mg group, and none in the placebo group. The only serious adverse event reported for two or more patients in any group was ulcerative colitis (one in each of the ABX464 100 mg and 50 mg groups, and three [5%] in the placebo group). INTERPRETATION: All doses of ABX464 significantly improved moderate-to-severe, active ulcerative colitis compared with placebo, as measured by changes in MMS from baseline to week 8. A phase 3 clinical programme is ongoing. FUNDING: Abivax.

Safety and efficacy of the miR-124 upregulator ABX464 (obefazimod, 50 and 100 mg per day) in patients with active rheumatoid arthritis and inadequate response to methotrexate and/or anti-TNFα therapy: a placebo-controlled phase II study.

OBJECTIVE: This phase 2a randomised, double blind, placebo controlled, parallel group study evaluated the safety and efficacy of a first-in-class drug candidate ABX464 (obefazimod, 50 mg and 100 mg per day), which upregulates the biogenesis of the mRNA inhibitor micro-RNA (miR)-124, in combination with methotrexate (MTX) in 60 patients (1:1:1 ratio) with moderate-to-severe active rheumatoid arthritis (RA) who have inadequate response to MTX or/and to an anti-tumour necrosis factor alpha (TNFα) therapy. METHODS: The primary end point was the safety of ABX464; efficacy endpoints included the proportion of patients achieving American College of Rheumatology (ACR)20/50/70 responses, disease activity scores (DAS) 28, simplified disease activity score, clinical disease activity score), European League Against Rheumatism response, DAS28 low disease activity or remission. RESULTS: ABX464 50 mg was safe and well tolerated. Two serious adverse events were reported (one on placebo group and one on ABX464 100 mg). Eleven patients were withdrawn for AEs (9 patients on 100 mg, 1 on 50 mg and 1 on placebo). Drug discontinuation was mainly due to gastrointestinal disorders. No cases of opportunistic infection, no malignancies and no death were reported. Compared with placebo, ABX464 50 mg showed significantly higher proportions of patients achieving ACR20 and ACR50 responses at week 12. DAS28-C reactive protein (CRP) and DAS28-erythrocyte sedimentation rate decreased significantly and rates of categorical DAS28-CRP response or CDAI remission increased significantly on ABX464 at week 12. A significant upregulation of miR-124 was observed in blood for every patient dosed with ABX464. CONCLUSION: ABX464 50 mg was safe, well tolerated and showed a promising efficacy. Mild-to-moderate gastrointestinal AEs led to a high drop-out rate of patients on ABX464 100 mg, which may not be a relevant dose to use. These findings warrant exploration of ABX464 at 50 mg per day or less for treating patients with RA. TRIAL REGISTRATION NAME: Phase IIa randomised, double blind, placebo controlled, parallel group, multiple dose study on ABX464 in combination with MTX, in patients with moderate to severe active RA who have inadequate response to MTX or/and to an anti- TNFα therapy or intolerance to anti-TNFα therapy.EUDRACT number: 2018-004677-27 TRIAL REGISTRATION NUMBER: NCT03813199.

A randomised, double-blind clinical phase II trial of the efficacy, safety, tolerability and pharmacokinetics of a single dose combination treatment with artefenomel and piperaquine in adults and children with uncomplicated Plasmodium falciparum malaria.

BACKGROUND: The clinical development of a single encounter treatment for uncomplicated malaria has the potential to significantly improve the effectiveness of antimalarials. Exploratory data suggested that the combination of artefenomel and piperaquine phosphate (PQP) has the potential to achieve satisfactory cure rates as a single dose therapy. The primary objective of the study was to determine whether a single dose of artefenomel (800 mg) plus PQP in ascending doses is an efficacious treatment for uncomplicated Plasmodium falciparum malaria in the 'target' population of children ≤ 5 years of age in Africa as well as Asian patients of all ages. METHODS: Patients in six African countries and in Vietnam were randomised to treatment with follow-up for 42-63 days. Efficacy, tolerability, safety and pharmacokinetics were assessed. Additional key objectives were to characterise the exposure-response relationship for polymerase chain reaction (PCR)-adjusted adequate clinical and parasitological response at day 28 post-dose (ACPR28) and to further investigate Kelch13 mutations. Patients in Africa (n = 355) and Vietnam (n = 82) were included, with 85% of the total population being children < 5 years of age. RESULTS: ACPR28 in the per protocol population (95% confidence interval) was 70.8% (61.13-79.19), 68.4% (59.13-76.66) and 78.6% (70.09-85.67) for doses of 800 mg artefenomel with 640 mg, 960 mg and 1440 mg of PQP respectively. ACPR28 was lower in Vietnamese than in African patients (66.2%; 54.55-76.62 and 74.5%; 68.81-79.68) respectively. Within the African population, efficacy was lowest in the youngest age group of ≥ 0.5 to ≤ 2 years, 52.7% (38.80-66.35). Initial parasite clearance was twice as long in Vietnam than in Africa. Within Vietnam, the frequency of the Kelch13 mutation was 70.1% and was clearly associated with parasite clearance half-life (PCt1/2). The most significant tolerability finding was vomiting (28.8%). CONCLUSIONS: In this first clinical trial evaluating a single encounter antimalarial therapy, none of the treatment arms reached the target efficacy of > 95% PCR-adjusted ACPR at day 28. Achieving very high efficacy following single dose treatment is challenging, since > 95% of the population must have sufficient concentrations to achieve cure across a range of parasite sensitivities and baseline parasitaemia levels. While challenging, the development of tools suitable for deployment as single encounter curative treatments for adults and children in Africa and to support elimination strategies remains a key development goal. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02083380 . Registered on 7 March 2014.

Efavirenz Capsule Sprinkle and Liquid Formulations With Didanosine and Emtricitabine in HIV-1-infected Infants and Children 3 Months to 6 Years of Age: Study AI266-922.

BACKGROUND: AI266-922 was an open-label, dose-ranging study that assessed the pharmacokinetics, safety and efficacy of efavirenz (EFV) in children (3 months to 6 years). METHODS: Antiretroviral-naïve and antiretroviral-experienced HIV-1-infected children received once-daily EFV as oral solution or capsule sprinkle plus didanosine and emtricitabine (FTC). Pharmacokinetic analyses were undertaken at week 2 and repeated at weeks 10 and 18 after an EFV dose change or switch from oral solution to capsule sprinkle. RESULTS: Thirty-seven subjects were treated. EFV area under the plasma concentration-time curve over 1 dosing interval from time 0 to 24 hours postdose values were generally suboptimal (<110 µM × h) in subjects younger than 3 years treated with oral solution; these subjects switched to capsule sprinkle. Twenty of 21 subjects younger than 3 years treated with capsule sprinkle achieved an EFV area under the plasma concentration-time curve over 1 dosing interval from time 0 to 24 hours postdose value >110 µM × h, although higher initial doses were administered in this age group. Interpatient variability in EFV exposure was high. By week 48, 77.8% and 63.0% of subjects achieved HIV-RNA <400 and <50 copies/mL, respectively. Median changes in log10 HIV-RNA and CD4 percentage from baseline were -3.18 copies/mL and +6%, respectively. Two (5.4%) patients discontinued because of adverse events (AEs). Serious AEs occurred in 20 (54.1%) subjects. Common AEs were diarrhea (49%), nasopharyngitis (35%) and pneumonia (30%). Overall, 43% of subjects with suboptimal EFV exposure at week 2 developed resistance. CONCLUSIONS: Once-daily EFV, given as capsule sprinkle, achieved target exposures in this study although doses were 2-3 times higher than Food and Drug Administration-approved doses for children younger than 3 years. These data are useful for dose selection modeling and simulation; however, Food and Drug Administration-approved doses should be used clinically. EFV + didanosine + FTC was efficacious with no new pediatric safety findings reported.

PRINCE-1: safety and efficacy of atazanavir powder and ritonavir liquid in HIV-1-infected antiretroviral-naïve and -experienced infants and children aged ≥3 months to <6 years.

INTRODUCTION: PRINCE-1 is an ongoing prospective, international, multicentre, nonrandomized, two-stage clinical trial assessing safety and efficacy of once-daily atazanavir (ATV) powder boosted with ritonavir (RTV) liquid plus optimized dual nucleoside reverse-transcriptase inhibitor (NRTI) background therapy in antiretroviral (ARV)-naïve and -experienced children with HIV-1 infection aged ≥3 months to <6 years. METHODS: Children with HIV-1 infection without prior ATV exposure and with a screening HIV-1 RNA ≥1000 copies/mL were enrolled. The dosing of ATV powder, boosted with 80 mg RTV liquid, was based on three baseline weight bands (5 to <10 kg=150 mg, 10 to <15 kg=200 mg and 15 to <25 kg=250 mg). RESULTS: Of the 56 treated patients, 46 completed 48 weeks of therapy, 67.9% were from Africa and 60.7% were ART-naïve. Median ages at baseline were 6, 35 and 55 months, and proportions with HIV-1 RNA >100,000 were 85.7, 52.6 and 25% in the three baseline weight bands, respectively. No unexpected safety events occurred and no deaths were reported. Over 48 weeks, upper respiratory tract infections, diarrhoea, vomiting and Grade 3 to 4 hyperbilirubinaemia occurred in 35.7, 35.7, 28.6, and 9.4% of patients, respectively; five patients (8.9%) discontinued due to adverse events (AEs); and 11 patients (19.6%) experienced serious adverse events. At Week 48, using a modified intent-to-treat analysis (two patients were excluded because they switched to ATV capsules before Week 48), 61.1 and 74.1% of patients overall had an HIV-1 RNA level <50 copies/mL and <400 copies/mL, respectively. Virologic suppression rates increased across the lowest to highest baseline weight bands (47.6, 68.4 and 71.4% had HIV-1 RNA <50 copies/mL, and 66.7, 73.7 and 85.7% had HIV-RNA <400 copies/mL, respectively) but did not differ meaningfully between ARV-naïve and -experienced patients. Overall, the median change from baseline in CD4 cell count was +363 cells/mm(3), and the median change from baseline in CD4 percent was +7.5%. CONCLUSIONS: ATV powder boosted with RTV liquid once daily plus optimized dual NRTI background therapy was effective and well tolerated in this ART-naïve or -experienced paediatric population aged ≥3 months to <6 years. No unexpected safety findings compared with those from previous ATV paediatric and adult studies were identified.

Safety and Effectiveness of Palivizumab in Children at High Risk of Serious Disease Due to Respiratory Syncytial Virus Infection: A Systematic Review.

INTRODUCTION: Lower respiratory tract infection (LRTI) is the leading cause of infant mortality globally in post-neonatal infants (i.e., 28-364 days of age). Respiratory syncytial virus (RSV) is the most commonly identified pathogen for infant LRTI and is the second most important cause of death in post-neonatal infants. Despite 50 years of RSV vaccine research, there is still no approved vaccine. Therefore, passive immunity with the monoclonal antibody palivizumab is the sole regulatory-approved option for the prevention of serious LRTI caused by RSV in pediatric patients at high risk of RSV disease. METHODS: We conducted a comprehensive systematic literature review of randomized controlled trials (RCTs), open-label non-comparative clinical trials, and prospective observational studies/registries, and summarized the evidence related to the safety, efficacy, and effectiveness of palivizumab. RESULTS: The efficacy of palivizumab, as measured by the relative reduction in RSV-related hospitalization rate compared with placebo ranged from 39% to 78% (P < 0.05) in the 2 pivotal RCTs. A meta-analysis of the RSV-related hospitalization rate from 5 randomized placebo-controlled trials yielded an overall odds ratio of 0.41 (95% CI, 0.31-0.55) in favor of palivizumab prophylaxis over placebo (P < 0.00001). Low rates of RSV-related hospitalizations were observed in palivizumab recipients consistently over time in more than 42,000 pediatric subjects across 7 RCTs, 4 open-label non-comparative trials, and 8 observational studies/registries conducted in 34 countries. In addition, among palivizumab-prophylaxed subjects with breakthrough RSV LRTI, rates of intensive care unit admission and mechanical ventilation from RSV hospitalization also were low and consistent across studies. With respect to safety, no differences were observed between palivizumab and placebo in the blinded RCTs. CONCLUSION: Rates of RSV hospitalizations and RSV hospitalization-related endpoints in pediatric subjects who received prophylaxis with palivizumab were low and constant over time and across RCTs, open-label non-comparative trials, and observational studies/registries.

A randomized comparative 96-week trial of boosted atazanavir versus continued boosted protease inhibitor in HIV-1 patients with abdominal adiposity.

BACKGROUND: Abdominal adiposity in HIV-1 patients initiating antiretroviral therapy may be part of a restoration-to-health phenomenon. Lipoatrophy is associated with long-term thymidine analogue therapy. Individual protease inhibitors (PIs) differ in their effects on lipids and insulin resistance. METHODS: A randomized open-label multicentre 96-week trial compared changes in fat distribution in patients with suppressed HIV-1 RNA and abdominal adiposity, who either continued on their current twice-daily ritonavir-boosted PI (PI/r) or switched to once-daily boosted atazanavir (ATV/r). Treatment with two nucleoside reverse transcriptase inhibitors was unchanged. Body composition was assessed by dual-energy x-ray absorptiometry (DEXA) and abdominal computerized tomography (CT) scanning. RESULTS: In total, 201 patients were randomized; 131 switched to ATV/r. Viral suppression (<50 copies/ml) was similarly maintained (93% ATV/r versus 89% PI/r). Mean changes from baseline in trunk-to-limb fat ratio were similar; difference estimates 0.03 (95% CI -0.06, 0.12; P=0.48 at week 48) and 0.02 (95% CI -0.10, 0.14; P=0.73 at week 96). More patients in the PI/r arm had a decrease of ≥20% in limb fat from baseline at week 96. Significantly greater reductions in proatherogenic lipids occurred following switch to ATV/r. Both treatment regimens were generally well-tolerated; the incidence of grade 3-4 treatment-related clinical adverse events was 34% among ATV/r recipients versus 4% of PI/r-treated patients. CONCLUSIONS: Switching to ATV/r had no demonstrable benefit on abdominal adiposity. Maintenance of efficacy, less limb fat loss and marked reduction in proatherogenic lipids was observed with ATV/r compared with continuing a PI/r regimen.

Unboosted atazanavir-based therapy maintains control of HIV type-1 replication as effectively as a ritonavir-boosted regimen.

BACKGROUND: Triple combination therapy based on a ritonavir (RTV)-boosted protease inhibitor plus two nucleoside/nucleotide reverse transcriptase inhibitors (NRTIs) has improved outcomes in HIV type-1 (HIV-1)-infected patients. For patients unable to tolerate these regimens, alternative therapeutic approaches are needed. METHODS: We report a comparative, open-label study in treatment-naive patients who underwent initial induction treatment with a triple combination including RTV-boosted atazanavir (ATV; 300/100 mg once daily). Patients who achieved an HIV-1 viral load <50 copies/ml after the induction period were then randomized in the maintenance phase either to continue on current treatment or to switch to unboosted ATV 400 mg once daily (plus two NRTIs unchanged). RESULTS: A total of 252 patients entered the induction phase, of whom 172 were eligible for randomization in the maintenance phase (ATV/RTV n=85 and ATV n=87). The unboosted ATV regimen demonstrated non-inferior efficacy to the ATV/RTV regimen with 78% and 75% of patients, respectively, maintaining virological suppression (HIV-1 RNA <50 copies/ml) up to week 48 after randomization (difference estimate 2.9, 95% confidence interval -9.8-15.5). Time to virological failure and change from the end of the induction phase in mean CD4(+) T-cell counts were also similar between the treatment arms. Although both regimens were well-tolerated, unboosted ATV was associated with fewer adverse events, fewer total bilirubin abnormalities and an improved lipid profile compared with ATV/RTV. CONCLUSIONS: An HIV-1 combined treatment regimen based on unboosted ATV is a feasible treatment option for patients with established virological control who are unable to tolerate triple combination therapy including ATV/RTV.