Comparison of two biosimilarity studies of FKB327 with the adalimumab reference product: randomized phase 1 studies of single-blind, single-dose subcutaneous injection in healthy Japanese male participants

Background

FKB327 has been developed as a biosimilar of the adalimumab reference product (RP). We compared the pharmacokinetics (PK), safety, and immunogenicity of FKB327 with those of the adalimumab RP after a single dose by subcutaneous (SC) injection in Japanese male participants.

Methods

Two randomized, single-blind, single-dose studies were conducted in healthy Japanese male participants to compare PK characteristics between FKB327 and the RP. Study 1 included 130 participants who were randomized in a 1:1 ratio to receive a subcutaneous injection of 40 mg of either FKB327 or the RP into the abdomen. In Study 2, another 130 subjects were randomized in a 1:1 ratio to receive either drug as in Study 1, but the drug administration site was changed to the thigh. The primary PK endpoints of both studies were area under the concentration-time curve from time zero to the last measurable concentration (AUC_0-t) and maximum serum concentration; area under the concentration-time curve from time zero to 360 h was also evaluated as one of the primary endpoints in Study 1. Biosimilarity in terms of pharmacokinetics was determined if the 90% confidence interval of the mean difference in geometric mean ratio of all primary PK parameters was within the prespecified equivalence criteria (0.80–1.25). Immunogenicity and safety were also evaluated as secondary endpoints.

Results

The serum concentration-time profiles were comparable between the FKB327 and the RP treatment groups in both studies. Primary PK parameters were within the prespecified bioequivalence range in Study 2, although AUC_0-t was slightly outside the upper side of the range in Study 1. No differences in safety profile were observed in these studies. The incidence of anti-drug antibodies (ADAs) and impact of ADAs on PK profile were similar among the treatment groups in both studies.

Conclusion

Biosimilarity between FKB327 and the RP after a single 40-mg SC injection was confirmed in healthy Japanese male participants by modifying the study design.

Trial registration

jRCT2071200058 (https://jrct.niph.go.jp/en-latest-detail/jRCT2071200058, https://rctportal.niph.go.jp/en/detail?trial_id=jRCT2071200058) and jRCT2071200057 (https://jrct.niph.go.jp/en-latest-detail/jRCT2071200057, https://rctportal.niph.go.jp/en/detail?trial_id=jRCT2071200057). Retrospectively registered 25/11/2020.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40360-021-00545-3.

P1404A PHASE 2 OPEN-LABEL, SINGLE-ARM, FIRST JAPANESE STUDY OF TENAPANOR, A NOVEL PHOSPHATE ABSORPTION INHIBITOR, FOCUSING ON PILL BURDEN DECREASE IN PATIENTS WITH HYPERPHOSPHATEMIA UNDERGOING HEMODIALYSIS

Background and Aims

Phosphate binders (PB) are usually prescribed to dialysis patients with hyperphosphatemia. Several studies have reported that higher PB pill burden may reduce adherence and lead to insufficient phosphorus control. Tenapanor is an investigational, minimally absorbed, orally administered, non-binder, small-molecule that inhibits the sodium/hydrogen exchanger isoform 3 (NHE3) in development for the control of serum phosphorus. A previous Ph3 study sponsored by Ardelyx, Inc. (NCT02675998) showed a significant phosphorus decrease compared to the placebo in patients with hyperphosphatemia undergoing hemodialysis (HD) in the US. Tenapanor was expected to reduce PB pill burden since it is administered as one small pill, taken twice a day. This was the first study in Japanese HD patients, which aimed to confirm whether tenapanor reduces the pill burden of PB.

Method

This was a multicenter, open-label, single-arm Ph2 study. The study consists of a screening period, a 3-week observation period, and a 26-week treatment period. Patients whose serum phosphorus level was ≥ 3.5 and ≤ 7.0 mg/dL, taking at least two PB pills three times a day were enrolled. The patients started to receive 30 mg of tenapanor twice daily. The tenapanor dose could be reduced in a step-wise manner (60, 40, 20 and 10 mg/day) at the investigator’s discretion, based on GI tolerability. PB treatment was continued according to individual regimens, however, the dose could be adjusted appropriately to maintain serum phosphorus level within ±0.5 mg/dL from the baseline. The primary endpoint was an achievement of at least a 30% decrease in the mean of the total number of PB and tenapanor pills compared to the number of PB pills at baseline. The proportion of patients who achieved at least a 30 % decrease were tested using binomial test with a threshold level of 20% and a one-sided significance level of 0.025. The analysis was conducted using the data as of Dec25, 2019.

Results

The primary endpoint was met. Of 67 enrolled patients at the timing of analysis, 48 patients (71.6%, [95% CI: 59.3% - 82.0%], p<0.001) achieved a 30% decrease in the total number of PB and tenapanor pills, and of those, 35 patients (52.2%, [95% CI: 39.7% - 64.6%]) achieved a 50% decrease and 18 patients (26.9%) no longer required the use of any PB at week 26. Mean phosphorus levels were maintained during the study from 5.2 mg/dL at the baseline to 4.7 mg/dL at week 26. The most frequent adverse event was diarrhea (76.1%), which was mostly mild to moderate. Only four patients discontinued the study due to diarrhea. Serious adverse events were reported in five patients, only two of which were related to tenapanor (diarrhea and acute myocardial infarction).

Conclusion

Tenapanor was able to provide phosphorus control with significantly fewer pills compared to PB. AE profile was similar to previous US studies. This result suggests that tenapanor, a non-binder, phosphate absorption inhibitor that provides a novel approach to the management of hyperphosphatemia, could potentially improve drug adherence by reducing PB pill burden while maintaining effective phosphorus control.

Efficacy and safety of benralizumab in Japanese patients with severe, uncontrolled eosinophilic asthma

BACKGROUND

In the Phase III CALIMA trial, benralizumab significantly reduced asthma exacerbations, increased lung function, and alleviated symptoms for patients with severe, uncontrolled eosinophilic asthma. The aim of this subgroup analysis was to evaluate the efficacy and safety of benralizumab for Japanese patients in the CALIMA trial.

METHODS

CALIMA was a randomised, controlled trial of 1306 patients (aged 12-75 years; registered at ClinicalTrials.gov: NCT01914757) with severe asthma uncontrolled by medium- to high-dosage inhaled corticosteroids and long-acting β₂-agonists (ICS/LABA). Patients received 56 weeks' benralizumab 30 mg either every 4 weeks (Q4W) or every 8 weeks (Q8W; first three doses Q4W), or placebo Q4W. The primary analysis population was patients receiving high-dosage ICS/LABA with blood eosinophils ≥300 cells/μL. This subgroup analysis covered Japanese patients from this group.

RESULTS

Of 83 patients randomised in Japan, 46 were receiving high-dosage ICS/LABA and had blood eosinophils ≥300 cells/μL. Compared with placebo, benralizumab reduced the annual rate of asthma exacerbations by 66% (Q4W; rate ratio 0.34, 95% CI, 0.11-0.99) and 83% (Q8W; rate ratio 0.17, 95% CI, 0.05-0.60); increased prebronchodilator FEV₁ by 0.334 L (Q4W; 95% CI, 0.020-0.647) and 0.198 L (Q8W; 95% CI, -0.118 to 0.514); and decreased total asthma symptom score by 0.17 (Q4W; 95% CI, -0.82 to 0.48) and 0.24 (Q8W; 95% CI, -0.87 to 0.40). Percentages of adverse events were consistent with the overall CALIMA group.

CONCLUSIONS

Benralizumab reduced annual asthma exacerbations and symptoms, increased lung function, and was well-tolerated by Japanese patients with severe, uncontrolled eosinophilic asthma.