A phase 2a study investigating the effects of ritlecitinib on brainstem auditory evoked potentials and intraepidermal nerve fiber histology in adults with alopecia areata.

Reversible axonal swelling and brainstem auditory evoked potential (BAEP) changes were observed in standard chronic (9-month) toxicology studies in dogs treated with ritlecitinib, an oral Janus kinase 3/tyrosine kinase expressed in hepatocellular carcinoma family kinase inhibitor, at exposures higher than the approved 50-mg human dose. To evaluate the clinical relevance of the dog toxicity finding, this phase 2a, double-blind study assessed BAEP changes and intraepidermal nerve fiber (IENF) histology in adults with alopecia areata treated with ritlecitinib. Patients were randomized to receive oral ritlecitinib 50 mg once daily (QD) with a 4-week loading dose of 200 mg QD or placebo for 9 months (placebo-controlled phase); they then entered the active-therapy extension and received ritlecitinib 50 mg QD (with a 4-week loading dose of 200 mg in patients switching from placebo). Among the 71 patients, no notable mean differences in change from baseline (CFB) in Waves I-V interwave latency (primary outcome) or Wave V amplitude on BAEP at a stimulus intensity of 80 dB nHL were observed in the ritlecitinib or placebo group at Month 9, with no notable differences in interwave latency or Wave V amplitude between groups. The CFB in mean or median IENF density and in percentage of IENFs with axonal swellings was minimal and similar between groups at Month 9. Ritlecitinib treatment was also not associated with an imbalanced incidence of neurological and audiological adverse events. These results provide evidence that the BAEP and axonal swelling finding in dogs are not clinically relevant in humans.

Integrated Safety Analysis of Ritlecitinib, an Oral JAK3/TEC Family Kinase Inhibitor, for the Treatment of Alopecia Areata from the ALLEGRO Clinical Trial Program.

BACKGROUND: The ALLEGRO phase 2a and 2b/3 studies demonstrated that ritlecitinib, an oral JAK3/TEC family kinase inhibitor, is efficacious at doses of ≥ 30 mg in patients aged ≥ 12 years with alopecia areata (AA). OBJECTIVE: The objective of this study was to evaluate the safety of ritlecitinib in an integrated analysis of four studies in AA. METHODS: Two cohorts were analyzed: a placebo-controlled and an all-exposure cohort. Proportions and study size-adjusted incidence rates (IRs) of adverse events (AEs) of interest and laboratory abnormalities are reported. RESULTS: In the placebo-controlled cohort (n = 881; median exposure: 169 days), the proportion of ritlecitinib-treated patients with AEs was 70.2-75.4% across doses versus 69.5% in the placebo group; serious AEs occurred in 0-3.2% versus 1.9% for the placebo. A total of 19 patients permanently discontinued due to AEs (5 while receiving the placebo). In the all-exposure cohort (n = 1294), median ritlecitinib exposure was 624 days [2091.7 total patient-years (PY)]. AEs were reported in 1094 patients (84.5%) and serious AEs in 57 (4.4%); 78 (6.0%) permanently discontinued due to AEs. The most common AEs were headache (17.7%; 11.9/100 PY), severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) positive test (15.5%; 9.8/100 PY), and nasopharyngitis (12.4%; 8.2/100 PY). There were two deaths (breast cancer and acute respiratory failure/cardiorespiratory arrest). Proportions (IRs) were < 0.1% (0.05/100 PY) for opportunistic infections, 1.5% (0.9/100 PY) for herpes zoster, 0.5% (0.3/100 PY) for malignancies (excluding nonmelanoma skin cancer), and 0.2% (0.1/100 PY) for major adverse cardiovascular events. CONCLUSIONS: Ritlecitinib is well tolerated with an acceptable safety profile up to 24 months in patients aged ≥ 12 years with AA (video abstract and graphical plain language summary available). TRIAL REGISTRIES: ClinicalTrials.gov: NCT02974868 (date of registration: 11/29/2016), NCT04517864 (08/18/2020), NCT03732807 (11/07/2018), and NCT04006457 (07/05/2019).

Effects of mixing temperature on the extrusion rheological behaviors of rubber-based compounds.

In this study, rim strip (R) and sidewall (S) compounds were prepared at varying initial mixing temperatures. The effects of the mixing temperature on the extrusion rheological behaviors of the compounds were investigated, and the relationships between the compound structure and the extrusion rheological behaviors were studied. The results showed that the tensile stress relaxation rates of both R and S were more sensitive to the mixing temperature than the shear stress relaxation rate, and the former was affected by both the dispersion of carbon black (CB) and the actual molecular weight of the rubbers. Strain sweep results showed that R, which had a higher CB content, had a more obvious Payne effect than S. When the initial mixing temperature increased from 80 °C to 90 °C, both storage modulus (G') at a low shear strain and the ΔG' of R obviously decreased, indicating CB dispersion improvement. The S extrudates showed higher die swell ratios (B) than the R extrudates, and the former was more sensitive to mixing temperature. The main factors influencing the B of the R and S were the CB dispersity and the molecular weight, respectively. In addition, at high extrusion rates, a sharkskin phenomenon could be observed for the R extrudate surfaces, whereas the S extrudates were more likely to be integrally distorted.

Methods for Imputing Missing Efficacy Data in Clinical Trials of Biologic Psoriasis Therapies: Implications for Interpretations of Trial Results.

BACKGROUND: An issue in long-term clinical trials of biologics in psoriasis is how to handle missing efficacy data. This methodological challenge may not be understood by clinicians, yet can have a significant effect on the interpretation of clinical trials.

OBJECTIVE Evaluate the effects of different data imputation methods on apparent secukinumab response rates.

METHODS: Post hoc analyses were conducted on efficacy data from 2 phase III, multicenter, randomized, double-blind trials (FIXTURE and ERASURE) of secukinumab in moderate to severe plaque psoriasis. Per study protocols, missing data were imputed using strict non-response imputation (NRI), a highly conservative method that assumes non-response for all missing data. Alternative imputation methods (observed data, last observation carried forward [LOCF], modified NRI, and multiple imputation [MI]) were applied in this analysis and the resultant response rates compared.

RESULTS: Response rates obtained with each imputation method diverged increasingly over 52-weeks of follow-up. Strict NRI response estimates were consistently lower than those using the other methods. At week 52, Psoriasis Area and Severity Index (PASI) 90 rates for secukinumab 300 mg based on strict NRI were 9.2% (FIXTURE) and 8.7% (ERASURE) lower than estimates obtained using the least conservative method (observed data). Estimates obtained through LOCF and modified NRI were closest to those produced by MI, currently regarded as the most methodologically sophisticated approach available.

CONCLUSION: Awareness of differences in assumptions and limitations among imputation methods is necessary for well-informed interpretation of trial data.

J Drugs Dermatol. 2017;16(8):734-742.

Secukinumab long-term safety experience: A pooled analysis of 10 phase II and III clinical studies in patients with moderate to severe plaque psoriasis.

BACKGROUND: Secukinumab, a fully human anti-interleukin-17A monoclonal antibody, has demonstrated efficacy and safety in patients with moderate to severe plaque psoriasis. OBJECTIVE: We reviewed safety data from the secukinumab psoriasis phase II/III program. METHODS: Data were pooled from 10 phase II/III secukinumab psoriasis studies. RESULTS: Analysis included 3993 subjects; 3430 received secukinumab, representing 2725 subject-years (SYs) of exposure. Over 52 weeks, for secukinumab 300 mg, 150 mg, and etanercept, respectively, exposure-adjusted incidence rates (IRs) per 100 SYs were comparable across treatments for total adverse events (AEs; 236.1, 239.9, and 243.4, respectively); infections (91.1, 85.3, and 93.7, respectively); serious AEs (7.4, 6.8, and 7.0, respectively); serious infections (1.4, 1.1, and 1.4, respectively); malignant or unspecified tumors (0.77, 0.97, and 0.68, respectively); and adjudicated major adverse cardiovascular events (0.42, 0.35, and 0.34, respectively). AEs were not dose-related except for nonserious, mild/moderate, skin/mucosal candidiasis (IRs 3.55, 1.85, and 1.37 for secukinumab 300 mg, 150 mg, and etanercept, respectively). LIMITATIONS: There was a limited number of patients in comparator groups and the exposure to placebo was short. CONCLUSION: Secukinumab had a favorable safety profile, had no meaningful difference between the 300- and 150-mg doses and, in terms of safety, was comparable to etanercept over 52 weeks in patients with moderate to severe plaque psoriasis.