Efficacy and safety of CM310 in moderate-to-severe atopic dermatitis: A multicenter, randomized, double-blind, placebo-controlled phase 2b trial

Pharmacokinetics, Pharmacodynamics, Safety, and Tolerability of Stapokibart in Healthy Volunteers and Adult Subjects with Atopic Dermatitis

INTRODUCTION

Stapokibart, a novel humanized anti-interleukin (IL)-4 receptor alpha monoclonal antibody, inhibits the signaling of IL-4 and IL-13, which are key drivers of type 2 inflammation in atopic dermatitis (AD). This study aimed to assess the safety, tolerability, pharmacokinetics (PK), and pharmacodynamics (PD) of stapokibart in a randomized, double-blind, placebo-controlled single ascending dose (SAD) study and a multiple ascending dose (MAD) study.

METHODS

The SAD study enrolled 33 healthy male adults aged 18-65 years at a single center. The MAD study enrolled 39 patients with moderate-to-severe AD aged 18-70 years at seven centers. Enrolled subjects were randomized to subcutaneous (SC) doses of stapokibart (75-600 mg) or placebo. Serum thymus and activation-regulated chemokine (TARC) and total immunoglobulin E (IgE) were measured as PD biomarkers for stapokibart.

RESULTS

Similar PK characteristics were observed in healthy volunteers and subjects with AD after the initial administration. Stapokibart exhibited non-linear pharmacokinetics in both types of subjects. Following single doses, the mean maximum serum concentration (Cmax) ranged from 5.3 to 63.0 μg/mL, median Tmax ranged from 3.0 to 7.0 days, mean terminal half-life (t1/2z) ranged from 2.39 to 7.43 days, and mean apparent volume (Vz/F) ranged from 3.64 to 6.73 L in healthy subjects. The mean AUC accumulation ratio was 2.29 in subjects with AD after three doses of stapokibart 300 mg administered every 2 weeks. The median serum total IgE and TARC levels on day 43 decreased from baseline by 14.9-25.2% and 48.6-77.0%, respectively, among subjects with AD receiving three doses of stapokibart. No subjects developed grade ≥ 3 adverse events (AEs) or serious AEs or discontinued the study because of AEs. The incidence of AEs was similar between stapokibart and placebo groups.

CONCLUSION

Stapokibart showed favorable pharmacokinetics, pharmacodynamics, safety, and tolerability in the SAD and MAD studies. Based on these results, phase II and phase III trials of stapokibart have been performed in subjects with moderate-to-severe AD.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier NCT06161090 (29 November, 2023), NCT04893941 (15 May, 2021).

Treatment of atopic dermatitis: Recently approved drugs and advanced clinical development programs

Atopic dermatitis (AD) represents the most common skin disease characterized by heterogeneous endophenotypes and a high disease burden. In Europe, six new systemic therapies for AD have been approved: the biologics dupilumab (anti-interleukin-4 receptor (IL-4R) α in 2017), tralokinumab (anti-IL-13 in 2021), lebrikizumab (anti-IL-13 in 2023), and the oral janus kinase (JAK) inhibitors (JAKi) targeting JAK1/2 (baricitinib in 2020 in the EU) or JAK1 (upadacitinib in 2021 and abrocitinib in 2022). Herein, we give an update on new approvals, long-term safety, and efficacy. Upadacitinib and abrocitinib have the highest short-term efficacy among the approved systemic therapies. In responders, dupilumab and tralokinumab catch up regarding long-term efficacy and incremental clinical benefit within continuous use. Recently, the European Medicines Agency has released recommendations for the use of JAKi in patients at risk (cardiovascular and thromboembolic diseases, malignancies, (former) smoking, and age ≥65 years). Furthermore, we give an overview on emerging therapies currently in Phase III trials. Among the topical therapies, tapinarof (aryl hydrocarbon receptor), ruxolitinib (JAK1/2i), delgocitinib (pan-JAKi), asivatrep (anti-transient receptor potential vanilloid), and phosphodiesterase-4-inhibitors (roflumilast, difamilast) are discussed. Among systemic therapies, current data on cord-blood-derived mesenchymal stem cells, CM310 (anti IL-4Rα), nemolizumab (anti-IL-31RA), anti-OX40/OX40L-antibodies, neurokinin-receptor-1-antagonists, and difelikefalin (κ-opioid-R) are reported.

Interleukin antagonists for atopic dermatitis: a new era of therapy

INTRODUCTION

Over the last decade, increasing understanding of the immunopathogenesis of atopic dermatitis (AD) enabled the recognition of multiple therapeutic targets and subsequently the development of novel, highly effective systemic treatments, including interleukin (IL)-antagonists. To date, the IL-4Ra-inhibitor dupilumab and the IL-13 inhibitor tralokinumab have gained regulatory approval in Europe for the treatment of moderate-to-severe AD, while more than 70 new therapeutics are currently in development.

AREAS COVERED

In this review, we address the role of ILs in the pathogenesis of AD and provide an overview of the novel and investigational IL-antagonists, as regards their efficacy and safety on moderate-to-severe AD.

EXPERT OPINION

Current data have established IL-4 and IL-13 inhibitors as effective and safe for the treatment of moderate-to-severe AD, as regards the rapid control of flares as well as the long-term remission of the disease. Data regarding the efficacy and safety of other IL-inhibitors, including those targeting IL-31, IL-22, IL-33, IL-36 and IL-18, are accumulating. There is still an unmet need for real-world-evidence studies and head-to-head studies for both currently available and future agents in AD treatment. Establishing predictive biomarkers of treatment response in a disorder of such considerable heterogenicity might help physicians pursue a patient-tailored therapeutic response.

Monoclonal antibodies for moderate-to-severe atopic dermatitis: a look at phase III and beyond

INTRODUCTION

The understanding of atopic dermatitis (AD) pathogenesis has rapidly expanded in recent years, catalyzing the development of new targeted monoclonal antibody treatments for AD.

AREAS COVERED

This review aims to summarize the latest clinical and molecular data about monoclonal antibodies that are in later stages of development for AD, either in Phase 3 trials or in the pharmacopoeia for up to 5 years, highlighting the biologic underpinning of each drug's mechanism of action and the potential modulation of the AD immune profile.

EXPERT OPINION

The therapeutic pipeline of AD treatments is speedily progressing, introducing the potential for a personalized medical approach in the near future. Understanding how targeting pathogenic players in AD modifies disease progression and symptomatology is key in improving therapeutic choices for patients and identifying ideal patient candidates.

Emerging drugs for the treatment of atopic dermatitis: a focus on phase 2 and phase 3 trials

INTRODUCTION

Atopic dermatitis (AD) is an inflammatory skin condition that affects millions of pediatric and adult patients with well-studied impact on morbidity and quality of life. Management occurs in a stepwise fashion beginning with preventative measures before immunomodulators are introduced. However, challenges remain in treatment of moderate-to-severe atopic dermatitis that is refractory to first- and second-line treatments and there are only few topical anti-inflammatory options, especially for pediatric patients.

AREAS COVERED

New medications are required to address these gaps as lesions may persist despite treatment or patients may discontinue treatment due to actual or anticipated adverse effects of mainstay medications. Emerging research into the pathophysiology of AD and the immune system at large has provided opportunities for novel interventions aimed at stopping AD mechanisms at new checkpoints. Clinical trials for 36 agents currently in phase 2 or phase 3 are evaluated with particular focus on the studies for, B244, CBP-201, tapinarof, lebrikizumab, nemolizumab, amlitelimab, and rocatinlimab as they explore novel pathways and have some of the most promising results.

EXPERT OPINION

These clinical trials contribute to the evolution of AD treatment toward greater precision based on salient pathways with a particular focus on moderate-to-severe AD to enhance efficacy and minimize adverse effects.

Efficacy and safety of stapokibart (CM310) in uncontrolled seasonal allergic rhinitis (MERAK): an investigator-initiated, placebo-controlled, randomised, double-blind, phase 2 trial

Background

There is no trial to assess the benefits of periodically using biologics during the pollen season in patients with uncontrolled seasonal allergic rhinitis (SAR), who have moderate-to-severe symptoms even after standard-of-care. This trial aimed to evaluate the efficacy and safety of the add-on administration of stapokibart, a humanised monoclonal antibody that targets interleukin-4 receptor alpha, in patients with uncontrolled SAR.

Methods

In this investigator-initiated, randomised, double-blind, placebo-controlled trial, eligible patients received either stapokibart 600-300 mg weekly (QW), every 2 weeks (Q2W), or placebo QW for 4 weeks. All patients were given mometasone furoate nasal spray and loratadine throughout the trial. The primary endpoint was the mean change from baseline in daily reflective total nasal symptom score (rTNSS) during 2-week treatment. Secondary efficacy outcomes included: the mean change from baseline in daily rTNSS during 4-week treatment; the mean changes and the mean percentage changes from baseline during 2-week and 4-week treatment in 1) daily rTNSS and reflective total ocular symptom score (rTOSS), 2) morning (AM)/evening (PM) rTNSS and rTOSS, 3) AM instantaneous total nasal symptom score (iTNSS) and instantaneous total ocular symptom score (iTOSS), 4) individual nasal and ocular symptoms; the change from baseline in Rhinoconjunctivitis Quality of-Life Questionnaire score during 4-week treatment. Exploratory endpoints included the change of prespecified markers related to type 2 inflammation pre- and post-treatment. Safety, immunogenicity, and pharmacokinetics were also evaluated. This study is registered with www.clinicaltrials.gov (NCT05470647).

Findings

Between August 17, 2022, and December 28, 2022, 92 patients with uncontrolled SAR were enrolled from 4 centres in China and randomly assigned to receive stapokibart 600-300 mg QW (n = 31), stapokibart 600-300 mg Q2W (n = 30), or placebo QW (n = 31), of whom 86 (93%) completed the study. Both stapokibart Q2W and QW did not significantly improve mean change from baseline in daily rTNSS compared with placebo in 2 weeks. The least-squares (LS) mean differences (97.5% confidence interval [CI]) compared with placebo were -1.0 (-2.3, 0.2) in stapokibart Q2W group (p = 0.065) and -0.2 (-1.5, 1.0) in stapokibart QW group (p = 0.67). For the secondary outcomes, compared with placebo, stapokibart Q2W presented significant improvements in the mean percentage change from baseline in daily rTNSS in 2 weeks (LS mean difference -12.9%, 95% CI -25.3%, -0.4%, p = 0.043), as well as AM iTNSS over 2 weeks (LS mean difference -17.4%, 95% CI -31.0%, -3.8%, p = 0.013) and 4 weeks (LS mean difference -15.4%, 95% CI -29.0%, -1.9%, p = 0.026). Additionally, the nasal congestion score was significantly lower in stapokibart Q2W than placebo during 2-week (LS mean difference -0.4, 95% CI -0.7, -0.1, p = 0.014) and 4-week (LS mean difference -0.4, 95% CI -0.7, -0.04, p = 0.028) treatment. Treatment-emergent adverse events (TEAEs) occurred in 48% (15/31), 33% (10/30), and 61% (19/31) of patients receiving stapokibart QW, Q2W, and placebo, respectively. Most reported TEAEs were sinus bradycardia, hyperlipidaemia, and blood uric acid increased.

Interpretation

In this phase 2 trial, both stapokibart regimens had an acceptable safety and tolerability profile but did not significantly improve daily rTNSS in patients with uncontrolled SAR. The efficacy of stapokibart in patients with uncontrolled SAR is being further investigated in ongoing phase 3 trials (clinicaltrials.gov, NCT05908032).

Funding

Ministry of Science and Technology of the People's Republic of China; Ministry of Education of the People's Republic of China; National Natural Science Foundation of China; Chinese Academy of Medical Sciences.

Antibodies to watch in 2024

The 'Antibodies to Watch' article series provides an annual summary of commercially sponsored monoclonal antibody therapeutics currently in late-stage clinical development, regulatory review, and those recently granted a first approval in any country. In this installment, we discuss key details for 16 antibody therapeutics granted a first approval in 2023, as of November 17 (lecanemab (Leqembi), rozanolixizumab (RYSTIGGO), pozelimab (VEOPOZ), mirikizumab (Omvoh), talquetamab (Talvey), elranatamab (Elrexfio), epcoritamab (EPKINLY), glofitamab (COLUMVI), retifanlimab (Zynyz), concizumab (Alhemo), lebrikizumab (EBGLYSS), tafolecimab (SINTBILO), narlumosbart (Jinlitai), zuberitamab (Enrexib), adebrelimab (Arelili), and divozilimab (Ivlizi)). We briefly review 26 product candidates for which marketing applications are under consideration in at least one country or region, and 23 investigational antibody therapeutics that are forecast to enter regulatory review by the end of 2024 based on company disclosures. These nearly 50 product candidates include numerous innovative bispecific antibodies, such as odronextamab, ivonescimab, linvoseltamab, zenocutuzumab, and erfonrilimab, and antibody-drug conjugates, such as trastuzumab botidotin, patritumab deruxtecan, datopotamab deruxtecan, and MRG002, as well as a mixture of two immunocytokines (bifikafusp alfa and onfekafusp alfa). We also discuss clinical phase transition and overall approval success rates for antibody therapeutics, which are crucial to the biopharmaceutical industry because these rates inform decisions about resource allocation. Our analyses indicate that these molecules have approval success rates in the range of 14-32%, with higher rates associated with antibodies developed for non-cancer indications. Overall, our data suggest that antibody therapeutic development efforts by the biopharmaceutical industry are robust and increasingly successful.