Drug delivery options to increase patient adherence and satisfaction in the management of rheumatoid arthritis -- focus on subcutaneous tocilizumab

The Osmolality and Hemolysis of High-Concentration Monoclonal Antibody Formulations

PURPOSES

Highly concentrated monoclonal antibody (mAb) formulations for subcutaneous administration are becoming increasingly preferred within the biopharmaceutical industry for ease of use and improved patient compliance. A common phenomenon observed in the industry is that osmolality detected via freezing-point depression (FPD) in high-concentration mAb formulations is much higher than the theoretical concentrations, yet the occurrence of this phenomenon and its possible safety issues have been rarely reported.

METHODS

The current study summarized theoretical osmolality of U.S. Food and Drug Administration approved high-concentration mAb formulations and evaluated effects of high osmolality on safety using hemolysis experiments for the first time. Two mAbs formulated at 150 mg/mL were used as models and configured into two isotonic solutions: a, a theoretically calculated molarity in the isotonic range (H) and b, an osmolality value measured via the FPD in the isotonic range (I). The H and I formulations of each mAb were individually subjected to hemolysis experiments, and the hemolysis rates of the two formulations of the same mAb were compared. Besides, the effect of mAb concentration on osmolality detected by FPD was explored as well.

RESULTS

The results indicated that the hemolysis rates were similar between the H and I formulations of mAbs at the same sample addition volume, and the osmolality values increased approximately linearly with the increase in mAb concentration.

CONCLUSIONS

High osmolality for high-concentration mAb formulations would not affect product safety and the excipients could be added at relatively high levels to maintain product stability, especially for labile products.

Spray-Dried Monoclonal Antibody Suspension for High-Concentration and Low-Viscosity Subcutaneous Injection

Administration of highly concentrated monoclonal antibodies (mAbs) through injection is often not possible as the viscosity can be readily above 50 mPa·s when the concentration exceeds 150 mg/mL. Besides, highly concentrated mAb solutions always exhibit increased aggregation propensity and lower stability, which raise the difficulty for the successful development of highly concentrated mAb formulations. We hereby explored the possibility of suspension as another formulation form for high-concentration proteins to reduce viscosity and maintain stability. Specifically, we demonstrated that spray drying can serve as a process to prepare particles for suspension. Particles prepared from formulations with different mAb/trehalose mass ratios displayed good physical stability and antibody binding affinity, as indicated by circular dichroism, fluorescence spectroscopy, and surface plasmon resonance (SPR)-based bioassay analyses. During spray drying, a surface tension-dominated enrichment of mAb on the particle surface was observed, but this did not show a significant negative impact on mAb stability. Spray-dried particles were subsequently suspended into benzyl benzoate, and the resulting suspension showed good stability and a lower viscosity when compared to its counterpart solution. Furthermore, mAbs recovered from the suspension maintained their conformational structure. Our study demonstrated that the suspension displayed low viscosity and good physical stability, so it may offer novel opportunities for the preparation of highly concentrated protein formulations.

Effectiveness of subcutaneous tocilizumab in refractory adult Still's disease: report of three cases and a review of the literature

Adult Still's disease (ASD) is a systemic inflammatory disorder characterised by spiking fever, skin rash, arthritis, hepatosplenomegaly, and elevated inflammatory markers. Several proinflammatory cytokines, including interleukin (IL)-6, contribute to its pathogenesis. There have been some recent reports on the efficacy of tocilizumab (TCZ), a humanised anti-IL-6 receptor antibody, in the treatment of ASD refractory to conventional therapy. However, most of the evidence is for intravenous administration of TCZ, whereas subcutaneous injection is often preferred in terms of efficiency in cost and labour. We have experienced three patients whose ASD was refractory to corticosteroid and immunosuppressant therapy but showed a marked response to off-label use of subcutaneous TCZ (TCZ-SC). Patient 1 received TCZ-SC 162 mg on days 0 and 14 and every week thereafter. Patients 2 and 3 received TCZ-SC every 2 weeks. At the time of initiation of TCZ-SC, all three patients had elevated inflammatory markers and two had fever despite previous therapy. After the first TCZ-SC injection, the patients became afebrile within one day and inflammatory parameters (i.e. C-reactive protein and erythrocyte sedimentation rate) returned to normal within 2 weeks. None of the patients developed severe infection or other serious side effects during 104 weeks of follow-up. There have been only a limited number of case reports showing that TCZ-SC significantly improves refractory ASD during its active phase. Our experience with these patients suggests that TCZ-SC could, as well as offering cost efficiency in clinical practice, be a potent treatment option for refractory ASD.

Absence of Association Between Abatacept Exposure and Initial Infection in Patients With Juvenile Idiopathic Arthritis

OBJECTIVE

To assess the relationship between infection risk and abatacept (ABA) exposure levels in patients with polyarticular-course juvenile idiopathic arthritis (pJIA) following treatment with subcutaneous (SC) and intravenous (IV) ABA.

METHODS

Data from 2 published studies (ClinicalTrials.gov: NCT01844518, NCT00095173) of ABA treatment in pediatric patients were analyzed. One study treated patients aged 2-17 years with SC ABA and the other treated patients aged 6-17 years with IV ABA. Association between serum ABA exposure measures and infection was evaluated using Kaplan-Meier plots of probability of first infection vs time on treatment by ABA exposure quartiles and log-rank tests. Number of infections by ABA exposure quartiles was investigated.

RESULTS

Overall, 343 patients were included in this analysis: 219 patients received SC ABA and 124 patients received IV ABA. Overall, 237/343 (69.1%) patients had ≥ 1 infection over 24 months. No significant difference in time to first infection across 4 quartiles of ABA exposure levels was observed in the pooled (P = 0.45), SC (2-5 yrs: P = 0.93; 6-17 yrs: P = 0.48), or IV (P = 0.50) analyses. Concomitant use of methotrexate and glucocorticoids (at baseline and throughout) with ABA did not increase infection risk across the ABA exposure quartiles. There was no evidence of association between number of infections and ABA exposure quartiles. No opportunistic infections related to ABA were reported.

CONCLUSION

In patients aged 2-17 years with pJIA, no evidence of association between higher levels of exposure to IV ABA or SC ABA and incidence of infection was observed.

Sarilumab monotherapy compared with adalimumab monotherapy for the treatment of moderately to severely active rheumatoid arthritis: an analysis of incremental cost per effectively treated patient

Purpose

Treatment outcomes and direct medical costs were examined, from a US health payer perspective, of monotherapy with sarilumab 200 mg subcutaneous (SC) every 2 weeks (Q2W) vs adalimumab 40 mg SC Q2W/QW in adult patients with moderately to severely active rheumatoid arthritis who are intolerant of, inadequate responders to, or considered inappropriate candidates for continued methotrexate treatment.

Patients and methods

Short-term analysis was based on 24-week wholesale acquisition costs of drugs and treatment response observed in the MONARCH Phase III trial (NCT02332590) per American College of Rheumatology (ACR) 20/50 criteria and European League Against Rheumatism (EULAR) Moderate/Good Disease Activity Score 28-joint count erythrocyte sedimentation rate. Long-term analysis, which also considered drug administration and routine care costs, was conducted via a 6-month decision tree and a 1- to 10-year Markov model with microsimulation of patient profiles from the MOBILITY Phase III trial (NCT01061736). Utilities and quality-adjusted life-years (QALYs) were estimated by mapping 6-month ACR levels to a relative change in Health Assessment Questionnaire – Disability Index score and via published algorithms.

Results

For sarilumab and adalimumab, respectively, 24-week drug costs were $18,954 and $29,232, and costs per responder were $26,435 vs $50,055 on ACR20; $41,475 vs $98,425 on ACR50; and $22,511 vs $41,230 on EULAR Moderate/Good. Base case results at 10 years for total costs and QALYs were $176,977 and 2.75 for sarilumab and $212,136 and 2.61 for adalimumab, respectively. Sarilumab was consistently the more effective and cost-saving treatment across all short-term and long-term incremental analyses.

Conclusion

Sarilumab monotherapy was the economically dominant treatment on incremental cost per responder and incremental cost per QALY compared with adalimumab monotherapy. These results were maintained within the sensitivity analyses.

Elucidating the weak protein-protein interaction mechanisms behind the liquid-liquid phase separation of a mAb solution by different types of additives

Liquid-liquid phase separation (LLPS) has long been observed during the physical stability investigation of therapeutic protein formulations. The buffer conditions and the presence of various excipients are thought to play important roles in the formulation development of monoclonal antibodies (mAbs). In this study, the effects of several small-molecule excipients (histidine, alanine, glycine, sodium phosphate, sodium chloride, sorbitol and sucrose) with diverse physical-chemical properties on LLPS of a model IgG1 (JM2) solutions were investigated by multiple techniques, including UV-vis spectroscopy, circular dichroism, differential scanning calorimetry/fluorimetry, size exclusion chromatography and dynamic light scattering. The LLPS of JM2 was confirmed to be a thermodynamic equilibrium process with no structural changes or irreversible aggregation of proteins. Phase diagrams of various JM2 formulations were constructed, suggesting that the phase behavior of JM2 was dependent on the solution pH, ionic strength and the presence of other excipients such as glycine, alanine, sorbitol and sucrose. Furthermore, we demonstrated that for this mAb, the interaction parameter (k_D) determined at low protein concentration appeared to be a good predictor for the occurrence of LLPS at high concentration.

Preventive Effect of Lactobacillus helveticus SBT2171 on Collagen-Induced Arthritis in Mice

We recently reported that the intraperitoneal inoculation of Lactobacillus helveticus SBT2171 inhibited the development of collagen-induced arthritis (CIA), a murine model of rheumatoid arthritis (RA). In the present study, we evaluated the effect of the oral administration of L. helveticus SBT2171 on CIA development and on the regulation of antigen-specific antibody production and inflammatory immune cells, which have been implicated in the development of RA. Both oral administration and intraperitoneal inoculation of L. helveticus SBT2171 reduced joint swelling, body weight loss, and the serum level of bovine type II collagen (CII)-specific antibodies in the CIA mouse model. The intraperitoneal inoculation also decreased the arthritis incidence, joint damage, and serum level of interleukin (IL)-6. In addition, the numbers of total immune cells, total B cells, germinal center B cells, and CD4⁺ T cells in the draining lymph nodes were decreased following intraperitoneal inoculation of L. helveticus SBT2171. These findings demonstrate the ability of L. helveticus SBT2171 to downregulate the abundance of immune cells and the subsequent production of CII-specific antibodies and IL-6, thereby suppressing the CIA symptoms, indicating its potential for use in the prevention of RA.

Interleukin-6 (IL-6) Receptor Antagonist Protects Against Rheumatoid Arthritis

Background

The aim of this study was to investigate the protective effect of interleukin-6 (IL-6) receptor antagonist tocilizumab (TCZ) on rheumatoid arthritis (RA) and its related mechanism.

Material/Methods

Thirty RA patients receiving long-term methotrexate therapy at moderate and severe active stages were selected and treated with TCZ 8 mg/kg/time iv gtt intravenously guttae every 4 weeks. Peripheral blood was extracted before and 24 weeks after TCZ treatment. Peripheral blood mononuclear cells (PBMC) were collected by density gradient centrifugation. Flow cytometry was used to detect the ratio of CD4 naïve T cells and CD4 memory T cells, Th17 cells, and Treg cells in PBMC. DAS28 score, CRP, RF, and CCP levels in patients were evaluated.

Results

Compared with before treatment, IL-6 receptor antagonist TCZ significantly improved patients’ condition, including DAS28 score, CRP, RF, and CCP levels (P<0.01). Furthermore, TCZ obviously upregulated CD4 naïve T cells proportion and decreased CD4 memory T cells ratio (P<0.01). TCZ also markedly reduced the proportion of Th17 cells and increased the proportion of Treg cells (P<0.01).

Conclusions

TCZ can treat RA patients through regulating the ratio of CD4 naïve T cells, CD4 memory T cells, Th17 cells, and Treg cells in PBMC.

Subcutaneous tocilizumab for the treatment of rheumatoid arthritis

Rheumatoid arthritis (RA) is characterized by inflammatory synovitis and is mediated by several cytokines; this includes interleukin-6, whose receptor has been successfully targeted by the humanized monoclonal antibody tocilizumab. Intravenous tocilizumab (TCZ-IV) is registered for use in RA (alone or as combination therapy), systemic juvenile idiopathic arthritis and Castleman disease. Subcutaneous tocilizumab (TCZ-SC) is a desirable alternative to existing subcutaneous biological disease modifying antirheumatic drugs (bDMARDs) targeting tumor necrosis factor. TCZ-SC efficacy has been evaluated in three randomized controlled trials. BREVACTA demonstrated superiority to placebo, and both MUSASHI and SUMMACTA demonstrated non-inferiority to TCZ-IV. TCZ-SC has a similar safety profile to TCZ-IV apart from increased rates of injection site reactions and development of anti-TCZ antibodies (the latter of uncertain clinical significance). TCZ-SC 162 mg fortnightly is equivalent to TCZ-IV 4 mg/kg fourth weekly; TCZ-SC 162 mg weekly is equivalent to TCZ-IV 8 mg/kg fourth weekly. TCZ-SC is a suitable bDMARD for RA, particularly when monotherapy is preferred.

Biologic monotherapy in the treatment of rheumatoid arthritis

Biologics, possibly in combination with a conventional disease-modifying antirheumatic drug (DMARD) - preferably methotrexate (MTX), are used in accordance with the recommendations of the international rheumatological societies. However, in clinical practice, this recommendation is often problematic, as many rheumatologists know from personal experience. The quality of life of the patient is affected mainly by drug-induced intolerances (eg, MTX). Thus, the acceptance of the patient to treatment is often so inadequate that a discontinuation of the drug is necessary. In daily practice, approximately 30% of patients with biological therapy receive no concomitant DMARD according to the register data.