Population Pharmacokinetics of Ozoralizumab in Patients with Rheumatoid Arthritis

Ozoralizumab is a bispecific NANOBODY compound that binds tumor necrosis factor alpha (TNFα) and human serum albumin. Ozoralizumab inhibits the TNFα physiological activity while maintaining long-term plasma retention owing to its human serum albumin-binding ability. A population pharmacokinetic (PK) model was developed using data from 494 Japanese patients with rheumatoid arthritis in Phase II/III and Phase III trials to assess the effects of potential PK covariates. The ozoralizumab PK after subcutaneous administration was described using a 1-compartment model with first-order absorption and first-order elimination processes. A proportional error model was used for inter- and intra-individual variabilities, with covariance set between inter-individual variabilities of the apparent clearance and apparent distribution volume. Body weight, sex, antidrug antibody status, estimated glomerular filtration rate, and concomitant methotrexate use were identified as covariates for apparent clearance, while body weight and sex were covariates for apparent distribution volume in the final model. Body weight had the greatest effect on the PK of ozoralizumab, while the other covariates had minor effects. When administered at 30 mg every 4 weeks, the predicted steady-state plasma trough concentration in a patient weighing 83.2 kg exceeded the trough concentration required to maintain efficacy of ozoralizumab, and the estimated exposure in a patient weighing 42.5 kg did not exceed the mean exposure at 80 mg, a well-tolerated dose, throughout 52 weeks. We developed a population PK model that adequately described the ozoralizumab PK in Japanese patients with rheumatoid arthritis, and none of the evaluated covariates showed clinically relevant effects on the PK of ozoralizumab.

Structural, nonclinical, and clinical features of ozoralizumab: A novel tumour necrosis factor inhibitor

Tumour necrosis factor (TNF) inhibitors are currently the most widely used biological agents to treat rheumatoid arthritis. Ozoralizumab (OZR), a novel TNF inhibitor, is an antibody using variable heavy-chain domains of heavy-chain antibody (VHHs) and became the first VHH drug approved for the treatment of rheumatoid arthritis in September 2022. VHHs isolated from camelid heavy-chain antibodies can bind antigens with a single molecule. OZR is a trivalent VHH that consists of two anti-human TNFα VHHs and one anti-human serum albumin (anti-HSA) VHH. This review summarizes OZR's unique structural characteristics and nonclinical and clinical data. The clinical data outline the pharmacokinetics, efficacy, relationship between efficacy and pharmacokinetics, and safety of OZR, focusing on a Phase II/III confirmatory study (OHZORA trial).

Effect of extended dosing interval of anti-TNF-alpha NANOBODY® compound ozoralizumab in patients with low disease activity rheumatoid arthritis

OBJECTIVE

To evaluate the effect of extended dosing interval on the efficacy and safety of ozoralizumab in patients with rheumatoid arthritis (RA).

METHODS

In a long-term extension study (HOSHIZORA trial) for patients who had completed a phase II/III study with methotrexate (MTX) or a phase III study without MTX, the dosing interval of ozoralizumab was allowed to extend from every 4 weeks (Q4W) to every 8 weeks (Q8W), at the physician's discretion, for patients who had maintained DAS28-ESR <3.2 at the last two time points. The continuation rate, efficacy and safety were examined in patients who had completed 24 weeks after the change in the dosing interval by the data cut-off point.

RESULTS

Of the 32 patients who maintained DAS28-ESR <3.2 and changed the interval from Q4W to Q8W, 28 (87.5%) remained on Q8W for 24 weeks. At week 24, the percentages of patients who remained on Q8W and achieved DAS28-ESR <2.6 and <3.2 were 71.9% and 84.4%, respectively. No safety concerns were observed for 24 weeks in the Q8W group.

CONCLUSIONS

In patients with RA and maintained DAS28-ESR <3.2 with ozoralizumab, efficacy was sustained and well tolerated after the dosing interval was extended from Q4W to Q8W.

Efficacy and safety of anti-TNF multivalent NANOBODY® compound 'ozoralizumab' without methotrexate co-administration in patients with active rheumatoid arthritis: A 52-week result of phase III, randomised, open-label trial (NATSUZORA trial)

OBJECTIVES

The aim is to assess the efficacy and safety of a 52-week subcutaneous ozoralizumab treatment at 30 and 80 mg without methotrexate (MTX) in active rheumatoid arthritis.

METHODS

This randomised, open-label, multicentre phase III trial randomly allocated 140 patients in 2:1 ratio as subcutaneous ozoralizumab at 30 or 80 mg every 4 weeks for 52 weeks without MTX.

RESULTS

Both groups administered ozoralizumab at 30 and 80 mg showed good clinical improvement. The American College of Rheumatology response rates were high at Week 24 and maintained through 52 weeks. The ozoralizumab groups also showed good improvement in other end points, and improvements observed from Week 1 were maintained through 52 weeks. Improvements in many efficacy assessments were similar between doses. No deaths were reported, and serious adverse events occurred in a total of 20 patients in the ozoralizumab groups. Increased antidrug antibodies were observed in approximately 40% of patients in the ozoralizumab groups, and 27.7% of the patients in the 30 mg group were neutralising antibody-positive.

CONCLUSIONS

Ozoralizumab, at 30 and 80 mg, demonstrated significant therapeutic effects without MTX, and the efficacy was maintained for 52 weeks with active rheumatoid arthritis. Ozoralizumab showed an acceptable tolerability profile over 52 weeks.

Efficacy and safety of the anti-TNF multivalent NANOBODY® compound ozoralizumab in patients with rheumatoid arthritis and an inadequate response to methotrexate: A 52-week result of a Phase II/III study (OHZORA trial)

OBJECTIVE

To assess the efficacy and safety through a 52-week treatment with subcutaneous ozoralizumab at 30 or 80 mg in patients with active rheumatoid arthritis despite methotrexate therapy.

METHODS

This multicentre, randomized, placebo-controlled, double-blind, parallel-group confirmatory trial included a 24-week double-blind treatment period followed by a 28-week open-label treatment period. The double-blind treatment period randomized 381 (2:2:1) patients to placebo and ozoralizumab at 30 or 80 mg, and patients receiving placebo were re-randomized (1:1) to ozoralizumab at 30 or 80 mg in the open-label period.

RESULTS

The ozoralizumab groups showed good clinical improvement, with high American College of Rheumatology response rates at 52 weeks, as well as good improvements in other endpoints, which were observed from Day 3 and maintained through Week 52. Furthermore, the ozoralizumab groups showed a high remission rate in clinical and functional remission at Week 52. Serious adverse events occurred in a total of 23 patients in the ozoralizumab groups, without differences in incidence between doses.

CONCLUSIONS

Ozoralizumab demonstrated significant therapeutic effects and efficacy, which was maintained for 52 weeks. The safety profile was consistent with the evaluated results in interim analysis at Week 24, and ozoralizumab was well-tolerated up to Week 52.

Ozoralizumab: first Nanobody® therapeutic for rheumatoid arthritis

INTRODUCTION

Ozoralizumab (Nanozora), a novel TNF inhibitor, was first approved in Japan in September 2022 as a next-generation antibody for the treatment of rheumatoid arthritis (RA). Ozoralizumab potently inhibits TNF action through two human TNFα-binding domains, and a human serum albumin-binding domain that prolongs its plasma half-life enabling 4-week administration intervals. Its molecular weight is 38 kDa, which is one-fourth that of the conventional immunoglobulin G.

AREAS COVERED

Structural characteristics of ozoralizumab, preclinical findings, clinical data, and its recommended positioning in current RA treatments have been summarized.

EXPERT OPINION

Studies using mouse models have shown the rapid distribution of ozoralizumab in inflamed joint tissues, presumably because of its small molecular size and albumin-binding action. In clinical studies, remarkable improvements in clinical symptoms and patient-reported outcomes were observed 2 days after subcutaneous administration of 30 mg ozoralizumab with concurrent methotrexate therapy. Moreover, the efficacy and tolerability of the drug for up to 52 weeks, with or without methotrexate, were confirmed. Ozoralizumab is expected to be a highly practical option for patients with RA as a new type of TNF inhibitor with early symptom improvement despite subcutaneous administration.