BioDrugs

Correction to: Vestronidase Alfa: A Review in Mucopolysaccharidosis VII The article Vestronidase Alfa: A Review in Mucopolysaccharidosis VII, written by Emma H. McCafferty and Lesley J. Scott, was originally published Online First without open access.

PARP Inhibitors and the Evolving Landscape of Ovarian Cancer Management: A Review Abstract As a drug class, inhibitors of poly-(ADP-ribose) polymerase (PARP) have had their greatest impact on the treatment of women with epithelial ovarian cancers (EOC), in particular, those with the most common histological subtype, high-grade serous cancer, as it has high rates of homologous recombination (HR) deficiency. PARP inhibition exploits this cancer vulnerability by further disrupting DNA repair, thus leading to genomic catastrophe. Early clinical data demonstrated the effectiveness of PARP inhibition in women with recurrent EOC harbouring BRCA1/2 mutations and those with platinum-sensitive recurrences. Three PARP inhibitors (olaparib, niraparib, and rucaparib) are now approved for use in women with recurrent EOC. Based upon randomised controlled trials, PARP inhibitors are in use as "maintenance" therapy for those with platinum-sensitive and platinum-responsive recurrences (irrespective of BRCA1/2 mutation status). Among women with BRCA1/2 mutations (either germline or somatic), maintenance PARP inhibitor therapy for those with recurrence has led to a nearly fourfold prolongation of progression-free survival compared to placebo control. Those without BRCA1/2 mutations experience an approximately twofold increase in progression-free survival. The latest clinical data demonstrate that women with BRCA1/2 mutations who respond to first-line chemotherapy and go on to have maintenance olaparib experience a doubling of the rate of freedom from death at 3 years when compared to placebo (60% vs 27%). PARP inhibitors are also approved as active therapy for women with germline or tumour BRCA1/2 mutations and recurrent EOC treated with three or more prior lines of therapy. Apart from the presence of a BRCA1/2 mutation (germline or somatic) and clinical factors such as platinum sensitivity and responsiveness, other predictive biomarkers are not in routine clinical use. Assays to identify genomic aberrations caused by HR deficiency, or mutations in genes involved in HR, have not been sufficiently sensitive to identify all patients who benefit from treatment. The mechanisms of PARP-inhibitor resistance include restoration of HR through reversion mutations in HR genes, capable of re-establishing the DNA open-reading frame and leading to resumed HR function. Other mechanisms that sustain sufficient DNA repair may also be important. This review focuses on the rationale for the use of PARP inhibitors in EOC. The data that have shaped clinical research are presented, and the trials that have changed management standards are reviewed and discussed. Highlighted are the past and ongoing efforts to further improve and explore the use of PARP inhibitors in EOC.

Immunogenicity of Chimeric Antigen Receptor T-Cell Therapeutics Abstract Chimeric antigen receptor (CAR) T-cell immunotherapy has gained significant attention in the past decade due to its considerable potential in the treatment of various types of malignancies, particularly hematological. While success has been achieved in a number of studies, and two CAR-T-cell products were recently approved by the US Food and Drug Administration (FDA) and the European Medicines Agency (EMA) (YESCARTA®, KYMRIAH®), this treatment modality continues to present challenges for clinical development. One major potential side effect is the ability of CAR-T products to induce host immune responses. Immunogenicity induction risk factors have been shown to be associated with the presence of non-human or partially human sequences in the CAR construct, suicide domain, or other components of the CAR-T, and also with the presence of residual viral proteins or other non-human origin proteins utilized as part of the gene editing step of CAR-T production. Both humoral (antibody-based) and cellular-type responses have been described, leading to various degrees of impact on CAR-T expansion and persistence, and therefore the overall safety and clinically meaningful response of the treatment. In this article we discuss various types of immune responses specific to CAR-T therapy, their impact on treatment outcome, and methodologies used to detect them.

Different Policy Measures and Practices between Swedish Counties Influence Market Dynamics: Part 1—Biosimilar and Originator Infliximab in the Hospital Setting Abstract Background Decentralisation of healthcare budgets and issuance of local guidelines means that the use of biosimilars can vary by region within a particular country, for example between the 21 counties of Sweden. Objectives This study aimed to analyse the county-level market dynamics of biosimilar and originator infliximab, which are hospital products, and to examine how local policy measures and practices, in addition to national policy, influenced market dynamics. Methods We first conducted a literature review on (biosimilar) policies in Sweden, then analysed market data provided by IQVIA™ on uptake of originator and biosimilar infliximab within the different counties (Q2 2012 to Q4 2017), including discounts from (tender) contracts. Biosimilar market shares were calculated with volume data (measured as defined daily doses [DDDs]). We then discussed our findings in semi-structured interviews with the national pricing and reimbursement agency, key experts within the county councils of Skåne, Västra Götaland, and Stockholm, and an industry representative. Results Market shares of biosimilar infliximab vary widely between counties (range 18–96% in 2017). The initial uptake of biosimilar infliximab was slow and variable, with abrupt increments in biosimilar market shares coinciding with expiration of contracts for the originator product. Different approaches taken by counties to achieve a low cost per DDD of infliximab were identified, i.e., a rapid switch to the biosimilar (Skåne), a delayed switch to the biosimilar (Stockholm), or no switch to the biosimilar when a favourable price on the originator product could be obtained (Västra Götaland). Quantitative analysis showed that 59% of the variability in biosimilar market shares could be explained by the relative difference in discounted price between the biosimilar and the originator product. In addition, qualitative analysis indicated the presence of key opinion leaders, local guidelines and initiatives, and whose budget it affects as drivers in the decision-making process. Conclusions Variations in the market share of biosimilar infliximab between the Swedish counties is largely explained by the discounted price difference between biosimilar and originator product, and counties used different strategies to leverage such biosimilar competition. Additionally, the presence of key opinion leaders, local guidelines and gainsharing arrangements appeared to play a role in infliximab market dynamics in counties.

A Global Phase I Clinical Study Comparing the Safety and Pharmacokinetics of Proposed Biosimilar BAT1706 and Bevacizumab (Avastin ® ) in Healthy Male Subjects Abstract Objective BAT1706 is a proposed biosimilar of bevacizumab (BEV). The objective of this phase I clinical trial was to establish pairwise similarity between BAT1706, US-sourced BEV (US-BEV), and EU-sourced BEV (EU-BEV) after a single intravenous (IV) infusion in healthy male subjects. Methods This phase I clinical trial was a randomized, double-blinded, three-arm study in 128 healthy adult male subjects. Every subject received a single IV infusion of 1 mg/kg of study drug and was subsequently monitored for 14 weeks. Pharmacokinetic, safety, and immunogenicity data were collected from each patient. The primary pharmacokinetic endpoint of this clinical study was area under the concentration curve from time zero to infinity (AUC0–inf). Biosimilarity of the study drugs was confirmed if the two-sided 90% confidence interval (CI) ratios of the geometric means for the three pairwise comparisons were contained within the range 80–125%. Other pharmacokinetic parameters including area under the concentration curve to time t (AUC0–t), maximum concentration of drug in plasma (Cmax), half-life (t½), and time to Cmax (tmax) were also measured. Results The pharmacokinetic parameters were comparable for the three drug products evaluated. The 90% CI for the AUC0–inf was 99–112% for BAT1706 versus EU-BEV, 97–110% for BAT1706 vs US-BEV and 92–104% for EU-BEV versus US-BEV comparisons, respectively, demonstrating biosimilarity. There were no significant adverse events attributable to BAT1706, as compared to EU-BEV and US-BEV. BAT1706 demonstrated a similar safety profile to EU-BEV and US-BEV. In addition, no anti-drug antibody positive result was reported for any subject included in the study. Conclusion In this study, BAT1706, a proposed biosimilar of BEV, was shown to be highly similar to EU-BEV and US-BEV in terms of pharmacokinetic equivalence, safety, and immunogenicity in healthy subjects after a single IV infusion. Trial Registration NCT03030430.

Adalimumab Biosimilars in Europe: An Overview of the Clinical Evidence Abstract Adalimumab, the first fully humanised monoclonal antibody against tumour necrosis factor alpha (TNF-α), has played a leading role in the revolution brought about by the introduction of biologics, and has received the widest range of indications among TNF-α inhibitors. Post-registration, observational and registry studies of real-life use have largely supported the outcomes seen in registrational clinical trials. With the recent loss of exclusivity for the originator medicinal product in Europe, a number of biosimilar adalimumab molecules have been licensed for use in the same indications as the originator molecule across rheumatology, dermatology, gastroenterology and ophthalmology. Clinicians in these areas first gained experience with biosimilar infliximab, followed by etanercept and rituximab. However, adalimumab is likely to present unique challenges given the numbers of patients treated and the range of biosimilar adalimumab products available. The biosimilar approval pathway has an emphasis on the pre-clinical analytic data in combination with clinical studies conducted to confirm therapeutic equivalence. To date, several adalimumab biosimilars have entered the EU market following successful marketing authorisation applications and recent expiration of originator patent protection. This overview covers the extent of use of adalimumab and summarises the regulatory process involved in the development of biosimilars as well as their use in clinical practice. The authors also discuss clinical data available so far on adalimumab biosimilars and their envisaged impact in the field of immune-mediated inflammatory diseases.

Assessing Analytical and Functional Similarity of Proposed Amgen Biosimilar ABP 980 to Trastuzumab Abstract Background ABP 980 has been developed as a biosimilar to Herceptin® (trastuzumab). Comprehensive analytical characterization incorporating orthogonal analytical techniques was used to compare ABP 980 to trastuzumab reference products sourced from the United States (US) and the European Union (EU). Methods Physicochemical property comparisons included the following: primary structure related to amino acid sequence and post-translational modifications, including glycans; higher-order structure; product-related substances and impurities, including size and charge variants; subvisible and submicron particles, and protein content. In addition, functional similarity was assessed for Fab-mediated, Fc-mediated, and combined Fab- and Fc-mediated activities. Results ABP 980 has the same amino acid sequence as and similar post-translational modification profiles to trastuzumab (US) and trastuzumab (EU). Importantly, ABP 980 was found to be highly similar to trastuzumab for all functional activities related to the mechanism(s) of action. Higher-order structure, product-related substances and impurities, particles and aggregates were also highly similar between ABP 980 and trastuzumab. Where minor differences were noted, they were evaluated and found unlikely to impact clinical performance. The totality of evidence, including the pharmacokinetic clinical similarity of ABP 980, further supports that ABP 980 is highly similar to trastuzumab. Conclusion Based on the comprehensive analytical similarity assessment, ABP 980 is analytically highly similar to the reference product, trastuzumab.

Different Policy Measures and Practices between Swedish Counties Influence Market Dynamics: Part 2—Biosimilar and Originator Etanercept in the Outpatient Setting Abstract Background Diverging approaches towards market entry and uptake of biosimilars, even within a country, leads to regional variation in biosimilar use. This is the case in Sweden, where the 21 county councils control the healthcare budget and offer regional guidance. Objectives This study aimed to analyse the market dynamics of originator and biosimilar etanercept (outpatient setting) in the different counties of Sweden, and examine the influence of local policy measures and practices, in addition to national policy. Methods This study was performed in three steps: (1) a structured review of the literature on (biosimilar) policies in Sweden; (2) analysis of market data on the counties' originator and biosimilar etanercept uptake (quarter two 2012 to quarter four 2017) provided by IQVIA™; and (3) discussion of findings in face-to-face semi-structured interviews with the national pricing and reimbursement agency, key experts in the county councils of Skåne, Västra Götaland and Stockholm, and an industry representative. Results Notwithstanding the existence of a national managed entry agreement for etanercept, wide variations in biosimilar market shares between counties were observed (40–82% in 2017). Over time, early and late adopters of biosimilar etanercept can be distinguished. In quarter four 2017, biosimilar market shares of all counties slightly decreased in accordance with the lower priced originator product from 1 October 2017. As prescriptions for treatment with etanercept are often provided for a year, two approaches are possible to switch patients: active pullback of prescriptions resulting in additional workload, or wait until the patient's next visit. Qualitative analysis indicated that the choice to use the biosimilar or the originator product depends on differences in rebated prices of the biosimilar and originator product, the presence of key opinion leaders, local guidelines, and financial streams and local gainsharing arrangements. Our estimates of current rebated prices and costs after gainsharing for the county councils and Government reveal only limited price differences between products. Conclusions Regional variations in use of biosimilar etanercept can be seen although prices are coordinated nationally. This suggests that counties react differently to price differences and highlights the role of local policy and attitudes of stakeholders towards biosimilars and switching. It seems that some counties are hesitant to switch patients, as it is associated with an increased administrative workload that might not be compensated for by savings associated with a lower priced product.

Physicochemical and Biological Characterization of RTXM83, a New Rituximab Biosimilar Abstract Background RTXM83 is a rituximab biosimilar with proven clinical safety and efficacy. It is the first rituximab biosimilar developed and approved in South America and is currently marketed in several Latin American, Middle Eastern and African countries. Objective The aim of this study was to present the physicochemical and biological characterization studies utilized to demonstrate the similarity between RTXM83 and its reference product. Methods Primary and higher order protein structures were analysed using peptide mapping with liquid chromatography–electrospray ionization–tandem mass spectrometry (LC–ESI–MS/MS), fluorescence spectroscopy and circular dichroism, and micro-differential scanning calorimetry, among other techniques. Charge variants were determined by cation-exchange chromatography (CEX) and capillary isoelectric focusing (cIEF). Glycosylation and glycoforms distribution were analysed using MS, normal phase high-performance liquid chromatography (NP-HPLC) and high-performance anion-exchange chromatography with pulsed amperometric detection (HPAE-PAD). Size variants were evaluated by size-exclusion chromatography (SEC), sedimentation velocity analytical ultracentrifugation (SV-AUC), dynamic light scattering (DLS), and capillary electrophoresis-sodium dodecyl sulfate (CE-SDS). Biological characterization included binding assays for complement C1q, CD20, and several Fc receptors (FcRs), as well as potency determination for in vitro apoptosis induction, complement-dependent cytotoxicity (CDC), and antibody-dependent cell-mediated cytotoxicity (ADCC). Results RTXM83 and the reference product showed identical primary sequences and disulfide bridge patterns, and similarity at higher order protein structures, post-translational modification profiles (amino acid modifications, charge variants, and glycosylation) and levels of purity and process-related impurities. Functional studies demonstrated that RTXM83 is similar to the reference product regarding the three known mechanisms of action of rituximab: CDC, ADCC, and apoptosis induction. Binding affinities to CD20, complement component C1q, and different FcRs were also equivalent. Conclusion RTXM83 is similar to its reference product in all critical quality attributes.

Analysis of Pharmacokinetic and Pharmacodynamic Parameters in EU- Versus US-Licensed Reference Biological Products: Are In Vivo Bridging Studies Justified for Biosimilar Development? Abstract Background Bridging studies are mandatory in the EU and USA if the reference biological product used in the biosimilar comparability exercise is foreign sourced. However, it has been argued that the duplication of bridging studies may limit biosimilar development. Objective The aim of the study was to explore whether it is necessary to conduct pharmacokinetic (PK)/pharmacodynamic (PD) bridging studies for biosimilars. This study examines similarities and differences between EU- and US-licensed reference biological products, based on literature-reported PK and/or PD data. Methods We searched PubMed, Drugs@FDA, and European Medicines Agency (EMA) databases to identify biosimilar bridging studies designed to evaluate similarities between EU- and US-licensed reference biological products. PK and/or PD parameters were retrieved; the ratio of the parameter value of the EU-licensed product to that of the US-licensed product and its corresponding 90% confidence intervals (CIs) were calculated. Similarity was declared if the 90% CIs for the ratios of the PK or PD parameters were within the range of 80–125%. Results Thirty-one bridging studies were identified for 11 biosimilars, including adalimumab (n = 10), bevacizumab (n = 4), epoetin alfa (n = 1), etanercept (n = 2), filgrastim (n = 1), infliximab (n = 3), insulin glargine (n = 1), insulin lispro (n = 1), PEGfilgrastim (n = 2), rituximab (n = 2), and trastuzumab (n = 4). Most studies showed PK and/or PD similarities between the EU- and US-licensed reference biological products. However, among the 31 studies, only three studies (accounting for two biologics, PEGfilgrastim and adalimumab) showed dissimilarity between the EU and US reference products. Although one bridging study on PEGfilgrastim (Sandoz) indicated dissimilar PKs (maximum observed plasma concentration [Cmax] and area under the concentration–time curve [AUC]) between the reference products, the other study (Mylan) demonstrated similar PK. Moreover, two of ten studies involving adalimumab failed to demonstrate similarities between the reference products. However, for both cases, PK similarities were later confirmed in the follow-up bridging studies with larger sample sizes. Conclusion Our analysis reveals that, in most cases, the reference biological products originated from the EU and those from the USA are almost indistinguishable in terms of PK/PD properties. Additional in vivo bridging studies between reference products from different global regions may not be required if similar physicochemical and structural properties are evident in vitro.

ALEXANDROS SFAKIANAKIS ANAPAFSEOS 5 AGIOS NIKOLAOS CRETE 72100 GREECE +306932607174 +302841026182