Regulatory perspectives of combination products

Integrated Devices: A New Regulatory Pathway to Promote Revolutionary Innovation

Policy Points Current medical device regulatory frameworks date back half a century and are ill suited for the next generation of medical devices that involve a significant software component. Existing Food and Drug Administration efforts are insufficient because of a lack of statutory authority, whereas international examples offer lessons for improving and harmonizing domestic medical device regulatory policy. A voluntary alternative pathway built upon two-stage review with individual component review followed by holistic review for integrated devices would provide regulators with new tools to address a changing medical device marketplace.

A Review of Recent FDA-Approved Biologic-Device Combination Products

With the remarkably strong growth of the biopharmaceutical market, an increasing demand for self-administration and rising competitions attract substantial interest to the biologic-device combination products. The ease-of-use of biologic-device combination products can minimize dosing error, improve patient compliance and add value to the life-cycle management of biological products. As listed in the purple book issued by the U.S. Food and Drug Administration (FDA), a total of 98 brand biologic-device combination products have been approved with Biologic License Application from January 2000 to August 2023, where this review mainly focused on 63 products containing neither insulin nor vaccine. Prefilled syringes (PFS) and autoinjectors are the most widely adopted devices, whereas innovative modifications like needle safety guard and dual-chamber design and novel devices like on-body injector also emerged as promising presentations. All 16 insulin products employ pen injectors, while all 19 vaccine products are delivered by a PFS. This review provides a systematic summary of FDA-approved biologic-device combination products regarding their device configurations, routes of administration, formulations, instructions for use, etc. In addition, challenges and opportunities associated with biologic-device compatibility, regulatory complexity, and smart connected devices are also discussed. It is believed that evolving technologies will definitely move the boundaries of biologic-device combination product development even further.

Research progress of implantation materials and its biological evaluation

With the development of modern material science, life science and medical science, implantation materials are widely employed in clinical fields. In recent years, these materials have also evolved from inert supports or functional substitutes to bioactive materials able to trigger or promote the regenerative potential of tissues. Reasonable biological evaluation of implantation materials is the premise to make sure their safe application in clinical practice. With the continual development of implantation materials and the emergence of new implantation materials, new challenges to biological evaluation have been presented. In this paper, the research progress of implantation materials, the progress of biological evaluation methods, and also the characteristics of biocompatibility evaluation for novel implantation materials, like animal-derived implantation materials, nerve contact implantation materials, nanomaterials and tissue-engineered medical products were reviewed in order to provide references for the rational biological evaluation of implantable materials.

Combinatorial islet protective therapeutic approaches in β-cell transplantation: Rationally designed solutions using a target product profile

While progress has been made in the development of islet cell transplantation (ICT) as a viable alternative to the use of exogenous insulin therapy in the treatment of type 1 diabetes, it has not yet achieved its full potential in clinical studies. Ideally, ICT would enable lifelong maintenance of euglycemia without the need for exogenous insulin, blood glucose monitoring or systemic immune suppression. To achieve such an optimal result, therapeutic approaches should simultaneously promote long-term islet viability, functionality, and localized immune protection. In practice, however, these factors are typically tackled individually. Furthermore, while the requirements of optimal ICT are implicitly acknowledged across numerous publications, the literature contains few comprehensive articulations of the target product profile (TPP) for an optimal ICT product, including key characteristics of safety and efficacy. This review aims to provide a novel TPP for ICT and presents promising tried and untried combinatorial approaches that could be used to achieve the target product profile. We also highlight regulatory barriers to the development and adoption of ICT, particularly in the United States, where ICT is only approved for use in academic clinical trials and is not reimbursed by insurance carriers. Overall, this review argues that the clear definition of a TPP in addition to the use of combinatorial approaches could help to overcome the clinical barriers to the widespread adoption of ICT for the treatment of type 1 diabetes.

Polymeric Gel Scaffolds and Biomimetic Environments for Wound Healing

Infected wounds that do not heal are a worldwide problem that is worsening, with more people dying and more money being spent on care. For any disease to be managed effectively, its root cause must be addressed. Effective wound care becomes a bigger problem when various traditional wound healing methods and products may not only fail to promote good healing. Still, it may also hinder the healing process, causing wounds to stay open longer. Progress in tissue regeneration has led to developing three-dimensional scaffolds (3D) or constructs that can be leveraged to facilitate cell growth and regeneration while preventing infection and accelerating wound healing. Tissue regeneration uses natural and fabricated biomaterials that encourage the growth of tissues or organs. Even though the clinical need is urgent, the demand for polymer-based therapeutic techniques for skin tissue abnormalities has grown quickly. Hydrogel scaffolds have become one of the most imperative 3D cross-linked scaffolds for tissue regeneration because they can hold water perfectly and are porous, biocompatible, biodegradable, and biomimetic. For damaged organs or tissues to heal well, the porosity topography of the natural extracellular matrix (ECM) should be imitated. This review details the scaffolds that heal wounds and helps skin tissue to develop. After a brief overview of the bioactive and drug-loaded polymeric hydrogels, the discussion moves on to how the scaffolds are made and what they are made of. It highlights the present uses of in vitro and in-vivo employed biomimetic scaffolds. The prospects of how well bioactiveloaded hydrogels heal wounds and how nanotechnology assists in healing and regeneration have been discussed.

Long-acting intrauterine systems: Recent advances, current challenges, and future opportunities

Levonorgestrel intrauterine systems (LNG-IUSs) are complex drug-device combination products designed to release a hormonal contraceptive drug for up to 7 years. These drug delivery systems offers a great promise as a modern method of long-acting reversible contraceptives (LARCs) to improve women's health. Unfortunately, there are some scientific challenges associated with the development of these products which are among the major reasons contributing to the availability of relatively few IUS products on the market. This review summarizes the formulation considerations (drug and excipient attributes), manufacturing methods, advances in characterization and in vitro drug release testing of IUSs, as well as factors influencing drug release from IUSs. A critical discussion on the major challenges to IUS product development is presented. Specifically, insights on bioequivalence evaluation, in vitro-in vivo correlation (IVIVC) establishment, and regulatory challenges are detailed. Lastly, methodological tools to overcome some of these hurdles to product development are proposed. The knowledge furnished through this review will be helpful towards obtaining better product understanding. Such understanding will facilitate the development of these complex drug products, as well as their regulatory approval process.

Translation of biomaterials from bench to clinic

Scientific research originates from curiosity and interests. Translational research of biomaterials should always focus on addressing specific needs of the targeted clinical applications. The guest editors of this special issue hope that the included articles have provided cutting-edge biomaterials research as well as insights of the translation of biomaterials from bench to clinic.

Advancing medical device regulatory reforms for innovation, translation and industry development in China

The blossoming Chinese medical device market calls for a science-based regulatory system in China. Consistent efforts have been made to advance the medical device regulatory reforms for innovation, translation and industry development. In this article, we report both the latest regulatory requirements which aim to ensure safety and efficacy for patients while encouraging innovation of the medical device industry, and the key programs on medical devices covered in the Regulatory Science Action Plan (RSAP) of the National Medical Products Administration of China (NMPA). The main features of the revised regulations are first elucidated before the opportunities for translational research are interpreted, including those for additive manufacturing and customized devices, drug–device combination products, artificial intelligence-powered software and surgical robots, and nanomaterials for medical devices. Finally, a regulatory perspective is provided to researchers who expect to translate their technologies in the Chinese medical device market. Important issues including early attention to critical market and clinical needs, understanding the true principle and spirit underlying the changing regulations and standards, and protecting intellectual property rights with comprehensive measures, are discussed. These developments warrant further investigations into the distinct role of regulatory science in shaping medical devices research and development.

Medicinal products meet medical devices: Classification and nomenclature issues arising from their combined use

When a medicinal product (MP) and a medical device (MD) are combined, their correct classification implies discrimination among different possible scenarios, based on the nature of the combination and the principal mechanism of action. In the European Union (EU), stakeholders deal with a lack of harmonization, which can represent an obstacle toward the development of these products, and a complex nomenclature, emerging from two divergent regulatory philosophies (i.e., that of MPs and that of MDs). In the USA, where the US Food and Drug Administration (FDA) supervises MDs, drugs, and biological products, stakeholders interact with a single authority, where any issue is addressed internally.

Drug-Eluting, Bioresorbable Cardiovascular Stents─Challenges and Perspectives

Globally, the leading causes of natural death are attributed to coronary heart disease and type 1 and type 2 diabetes. High blood pressure levels, high cholesterol levels, smoking, and poor eating habits lead to the agglomeration of plaque in the arteries, reducing the blood flow. The implantation of devices used to unclog vessels, known as stents, sometimes results in a lack of irrigation due to the excessive proliferation of endothelial tissue within the blood vessels and is known as restenosis. The use of drug-eluting stents (DESs) to deliver antiproliferative drugs has led to the development of different encapsulation techniques. However, due to the potency of the drugs used in the initial stent designs, a chronic inflammatory reaction of the arterial wall known as thrombosis can cause a myocardial infarction (MI). One of the most promising drugs to reduce this risk is everolimus, which can be encapsulated in lipid systems for controlled release directly into the artery. This review aims to discuss the current status of stent design, fabrication, and functionalization. Variables such as the mechanical properties, metals and their alloys, drug encapsulation and controlled elution, and stent degradation are also addressed. Additionally, this review covers the use of polymeric surface coatings on stents and the recent advances in layer-by-layer coating and drug delivery. The advances in nanoencapsulation techniques such as liposomes and micro- and nanoemulsions and their functionalization in bioresorbable, drug-eluting stents are also highlighted.

Clinical perspectives for repairing rotator cuff injuries with multi-tissue regenerative approaches

Background

In the musculoskeletal system, bone, tendon, and muscle form highly integrated multi-tissue units such as the rotator cuff complex, which facilitates functional and dynamic movement of the shoulder joint. Understanding the intricate interplay among these tissues within clinical, biological, and engineering contexts is vital for addressing challenging issues in treatment of musculoskeletal disorders and injuries.

Methods

A wide-ranging literature search was performed, and findings related to the socioeconomic impact of rotator cuff tears, the structure-function relationship of rotator cuff bone-tendon-muscle units, pathophysiology of injury, current clinical treatments, recent state-of-the-art advances (stem cells, growth factors, and exosomes) as well as their regulatory approval, and future strategies aimed at engineering bone-tendon-muscle musculoskeletal units are outlined.

Results

Rotator cuff injuries are a significant socioeconomic burden on numerous healthcare systems that may be addressed by treating the rotator cuff as a single complex, given its highly integrated structure-function relationship as well as degenerative pathophysiology and limited healing in bone-tendon-muscle musculoskeletal tissues. Current clinical practices for treating rotator cuff injuries, including the use of commercially available devices and evolving trends in surgical management have benefited patients while advances in application of stem/progenitor cells, growth factors, and exosomes hold clinical potential. However, such efforts do not emphasize targeted regeneration of bone-tendon-muscle units. Strategies aimed at regenerating bone-tendon-muscle units are thus expected to address challenging issues in rotator cuff repair.

Conclusions

The rotator cuff is a highly integrated complex of bone-tendon-muscle units that when injured, has severe consequences for patients and healthcare systems. State-of-the-art clinical treatment as well as recent advances have resulted in improved patient outcome and may be further enhanced by engineering bone-tendon-muscle multi-tissue grafts as a potential strategy for rotator cuff injuries.

Translational Potential of this Article

This review aims to bridge clinical, tissue engineering, and biological aspects of rotator cuff repair and propose a novel therapeutic strategy by targeted regeneration of multi-tissue units. The presentation of these wide-ranging and multi-disciplinary concepts are broadly applicable to regenerative medicine applications for musculoskeletal and non-musculoskeletal tissues.

An in silico trials platform for the evaluation of stent design effect in post-implantation outcomes

Bioresorbable Vascular Scaffolds (BVS), developed to allow drug deliver and mechanical support, followed by complete resorption, have revolutionized atherosclerosis treatment. InSilc is a Cloud platform for in silico clinical trials (ISCT) used in the design, development and evaluation pipeline of stents. The platform integrates beyond the state-of-the-art multi-disciplinary and multiscale models, which predict the scaffold's performance in the short/acute and medium/long term. In this study, a use case scenario of two Bioabsorbable Vascular Stents (BVSs) implanted in the same arterial anatomy is presented, allowing the whole InSilc in silico pipeline to be applied and predict how the different aspects of this intervention affect the success of stenting process.

Biological Evaluation of Medical Devices in the Form of Suppositories for Rectal and Vaginal Use

Background. Programs of preclinical safety studies of the health care products depend on the regulatory status of the investigated products. The classification of such products, in particular suppositories for rectal and vaginal use, is a critical step of developing tactics for their biological evaluation. Adaptation of biological evaluation methods for the medical devices based on the combination of biologically active substances, as well as evaluation of the results of such studies is urgent task of biomedicine. Objective. To substantiate the regulatory status and to carry out a biological evaluation of medical devices in the form of vaginal suppositories based on octenidine dihydrochloride ("Prodexyn") and in the form of rectal suppositories based on Saw palmetto, Levisticum officinale and Calendula officinalis extracts ("Pravenor"). Methods. Biological evaluation was conducted according to the requirements of ISO 10993 standards using in vitro and in vivo biological test systems (cytotoxicity in cell culture and the MTT test, sensitizing and irritating effect in guinea pigs). Results. The cytotoxicity (СС50) of the medical device "Prodexyn" extract in Vero cell culture was 8.35 μg/ml calculated as octenidine dihydrochloride and 416.65 μg/ml calculated as dexpanthenol. "Pravenor" medical device was found to be non-toxic in Vero cell culture. According to the results of MMT assay CC50 for octenidine dihydrochloride was 1.67 μg/ml, and 83.33 μg/ml – for dexpanthenol. CC50 indicators calculated for the different active ingredients of the medical device "Pravenor" were the following: 50 mg/ml for the dwarf palm berries extract (Saw palmetto), 16.67 mg/ml for the lovage roots extract (Levisticum officinale), and 16.67 mg/ml for the calendula flowers extract (Calendula officinalis). No sensitizing or skin irritating effects were observed in guinea pigs. Conclusions. Biological evaluation of medical devices in the form of rectal suppositories "Pravenor" and vaginal suppositories "Prodexyn" performed using in vitro and in vivo biological systems. It was demonstrated an acceptable level of safety of the products. The MTT test was 5 times more sensitive than the Vero cell culture method in determination of cytotoxicity.