Product Potency Research Articles

What health professionals should know about omega-3 fatty acid supplements

Omega-3 (n-3) fatty acids are essential to maintain satisfactory human health and need to be consumed in the diet. Western diets are often deficient in n-3 fatty acids because of an insufficient intake of cold water oily fish. The main n-3 fatty acids in fatty fish are eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). To date, no formally accepted dietary reference intakes for EPA and DHA exist, while international intake recommendations differ widely. Supplementation is an easy and convenient way of increasing dietary n-3 fatty acid intake, but very little information is available to health professionals when advising consumers on choosing a supplement to suit their lifestyle. Reliable nutrition information on product labels is vital since misleading information may lead to erroneous dosages with concomitant adverse effects. Since no formal regulatory structure for dietary supplements currently exists in South Africa, consumers depend on self-regulation within the industry for assurance of product quality, consistency, potency and purity of n-3 fatty acid supplements. Therefore, the aim of this article is to equip health professionals with proper knowledge with special reference to the bioavailability of fish oil supplements, reliability of labelling information, dietary intake recommendations, potential adverse effects and some general advice when purchasing n-3 fatty acid supplements.

Chemical and biological characterization of Food Allergy Herbal Formula 2 (FAHF-2) product consistency and potency

FAHF-2 has been shown to prevent peanut-induced anaphylaxis in a murine model. Phase I trials have demonstrated that FAHF-2 is a safe treatment for patients with food allergy. To complete the ongoing phase II study of safety and efficacy of FAHF-2, several batches of FAHF-2 were generated. The aim of this study was to analyze the chemical and biological consistency of different batches of FAHF-2 using our established methods. HPLC chromatogram data of each batch of FAHF-2 product were collected for analyzing product consistency. The bioactivities of 3 different batches of FAHF-2 (batch number1106, 0909 and 0202) were analyzed by culturingU266 (human B cell myeloma cell line), RBL-2H3 (mast cell line), and RAW 264.7 (mouse macrophage cell line) in the presence of 31, 62, 125, 250, and 500 μg/ml of FAHF-2. IgE production by U266, β-hexosaminidase release by RBL-2H3, and TNF-α production by RAW 264.7 cells were determined. Untreated cells were used as controls. Three biomarkers, berberine, jatrorrhizine, and ganoderic acid D, were used as indicators of FAHF-2 batch consistency. HPLC chromatogram data showed that batches of FAHF-2 had similar peak intensities of these three biomarkers. The in vitro assays showed that different batches of FAHF-2 all significantly inhibited IgE production by B cells, TNF-α production by macrophage cells, and degranulation by mast cells. IC50 values of 3 batches were comparable in the three bioactivity assays. This study shows that different batches of FAHF-2 used in clinical trials exhibited chemical consistency and biological potency in vitro.

Chemical Interference of Biological Systems with Natural Products

Chemical compounds isolated from natural sources offer unique opportunities to understand life on a molecular level. In this account, an overview over different natural products investigated in our research group over the last decade is presented. We have shown that protein localization in living cells can be controlled by anguinomycins and derivatives. Furthermore, a truncated analog, SB640, was discovered that retained much of the natural product potency. Detailed studies of the iron chelator anachelin led to the development of a bio-inspired platform for the generation of bioactive interfaces. The discovery of natural products isolated from cyanobacteria such as nostocarboline, aerucyclamides, cyanopetolin 1020 and various microcystins is presented and their molecular mechanisms of action were investigated. The last part describes the synthesis and evaluation of various natural products involved in neuritogenesis and synapse reconstruction such as withanolide A, militarinone, farinosone A and C and torrubiellone C. Their potential with regard to their use in regenerative medicine is discussed.

Analysis of omega-3 fatty acid content of South African fish oil supplements.

Substantial evidence describes the protective effects of marine-derived omega-3 (n-3) polyunsaturated fatty acids (PUFA) on cardiovascular diseases as well as many other conditions. Numerous fatty acid preparations are marketed for supplementing the Western diet, which is low in n-3 fats. Since these preparations may vary in their n-3 PUFA content, we tested 45 commercially available products on the South African market for their fatty acid composition. Forty-five commercially available n-3 fatty acid supplements were analysed using gas-liquid chromatography to determine their fatty acid content. More than half of the n-3 supplements available on the South African market contained ≤ 89% of the claimed content of EPA and/or DHA as stated on the product labels. To meet ISSFAL's recommendation of 500 mg EPA + DHA/day can cost consumers between R2 and R5 per person per day (R60 to R150 p/p/month). Regarding rancidity, the majority of capsules contained conjugated diene (CD) levels higher than that of vegetable oil obtained from opened containers (three months) used for domestic cooking purposes, despite the addition of vitamin E as antioxidant. Since no formal regulatory structure for dietary supplements currently exists in South Africa, consumers depend on self-regulation within the nutraceutical industry for assurance of product quality, consistency, potency and purity. Our results indicate that more than half of the n-3 fatty acid supplements on the South African market do not contain the claimed EPA and/or DHA contents as stated on product labels, and they contained CD levels higher than that in unused vegetable oils obtained from opened containers used for domestic cooking purposes.

U.S. FDA requirements for Human Vaccine Product Safety and Potency Testing

The Office of Vaccines Research and Review (OVRR) at the Center for Biologics Evaluation and Research (CBER), Food and Drug Administration (FDA) regulates preventative and therapeutic vaccines for infectious disease indications for use in humans. The framework for regulation of biological products includes Statutes (e.g. The U.S. Food, Drug and Cosmetic Act and the Public Health Service Act), regulations as defined in the Code of Federal Regulations (CFR) and guidance documents. Approval of a biologics license for a product, including vaccines, is based on a demonstration of safety, purity, and potency and assurance that the facility for manufacture, processing, and packaging meets standards to ensure that product released for distribution is safe, pure and potent. The regulatory definitions of safety, purity and potency are detailed in Title 21 of the Code of Federal regulations (CFR) Part 600. All manufacturing information including tests for safety, purity, and potency for a particular product must be documented in the Biologics License Application (BLA). Potency testing may be performed on the final bulk sample or final container sample and may consist of either in vivo or in vitro tests or both. To change a potency or safety test post-licensure requires a Supplement to the License and data to support a modified or alternative test. CBER encourages the development and use of appropriate alternative methods for vaccine safety and potency testing.

Gene-Modified Cellular Vaccines: Technologic Aspects and Clinical Problems

Activity in the cancer vaccine sector has quadrupled in the last decade. A number of therapeutic cancer vaccines are reaching the market. The huge number of clinical trials in progress is expected to undergo evaluation shortly. Whole cell tumor vaccines or gene-modified whole cells are being intensively tested in clinical trials. However, the specificity of the product makes the drug development process, including clinical trials, a considerable challenge. Their complex nature, standardization of manufacturing, and characterization often pose problems. Accordingly, to develop a well characterized controlled vaccine, more than a few factors need to be established. The final cell vaccine formulation must be characterized for product identity, purity, impurities, sterility, potency, cell viability, and total cell number. Therapeutic cancer vaccines show different clinical characteristics than cytotoxic anticancer agents. Unfortunately, the rules of clinical trial design for active immunotherapy have been adapted from the designs for examination of cancer chemotherapy. Accordingly, many research groups and clinical consortia have postulated modifications and unifications of existing clinical trial designs. A clinical development model has suggested that cancer vaccines be investigated in 2 categories of clinical trials: proof-of- principle and efficacy. Moreover, it is becoming clear that no drug demonstrates anticancer activity in all patients. Thus, intensive studies have been performed to seek specific biomarkers which could help stratify patients who are likely to respond to a particular treatment. This presents a big challenge beyond the analysis of the immune system status necessary to assess the effects of active immunotherapy.

Modeling the competition between aggregation and self‐assembly during virus‐like particle processing

Understanding and controlling aggregation is an essential aspect in the development of pharmaceutical proteins to improve product yield, potency and quality consistency. Even a minute quantity of aggregates may be reactogenic and can render the final product unusable. Self-assembly processing of virus-like particles (VLPs) is an efficient method to quicken the delivery of safe and efficacious vaccines to the market at low cost. VLP production, as with the manufacture of many biotherapeutics, is susceptible to aggregation, which may be minimized through the use of accurate and practical mathematical models. However, existing models for virus assembly are idealized, and do not predict the non-native aggregation behavior of self-assembling viral subunits in a tractable nor useful way. Here we present a mechanistic mathematical model describing VLP self-assembly that accounts for partitioning of reactive subunits between the correct and aggregation pathways. Our results show that unproductive aggregation causes up to 38% product loss by competing favorably with the productive nucleation of self-assembling subunits, therefore limiting the availability of nuclei for subsequent capsid growth. The protein subunit aggregation reaction exhibits an apparent second-order concentration dependence, suggesting a dimerization-controlled agglomeration pathway. Despite the plethora of possible assembly intermediates and aggregation pathways, protein aggregation behavior may be predicted by a relatively simple yet realistic model. More importantly, we have shown that our bioengineering model is amenable to different reactor formats, thus opening the way to rational scale-up strategies for products that comprise biomolecular assemblies.

Collaborative study for the validation of alternative in vitro potency assays for human tetanus immunoglobulins

An international collaborative study to validate 2 alternative in vitro methods for the potency testing of human tetanus immunoglobulin products was organised by the European Directorate for the Quality of Medicines & HealthCare (EDQM). The study, run in the framework of the Biological Standardisation Programme (BSP) under the aegis of the European Commission and the Council of Europe, involved 21 official medicines control and industry laboratories from 15 countries. Both methods, an enzyme-linked immunoassay (EIA) and a toxoid inhibition assay (TIA), showed good reproducibility, repeatability and precision. EIA and TIA discriminated between low, medium and high potency samples. Potency estimates correlated well and both values were in close agreement with those obtained by in vivo methods. Moreover, these alternative methods allowed to resolve discrepant results between laboratories that were due to product potency loss and reporting errors. The study demonstrated that EIA and TIA are suitable quality control methods for tetanus immunoglobulin, which can be standardised in a control laboratory using a quality assurance system. Consequently, the Group of Experts on Human Blood and Blood Products of the European Pharmacopoeia revised the monograph on human tetanus immunoglobulins to include both the methods as compendial alternatives to the in vivo mouse challenge assay.

Abstract 5608: Sipuleucel-T treatment results in sequential ex vivo activation of APCs and T cells during the culture step - evidence for in vivo immunological priming

Abstract Introduction. Sipuleucel-T is an investigational autologous immunotherapy for the treatment of prostate cancer. Product potency is measured in part by antigen presenting cell (APC) expression of CD54. Previous data have shown that CD54 upregulation correlates with APC activation (Sheikh 2008). This study investigated the ex vivo activation profile of T cells from men with metastatic castrate resistant prostate cancer enrolled in a Phase 3 study (D9902B, IMPACT) evaluating the safety and efficacy of sipuleucel-T treatment. Methods. Sipuleucel-T was prepared by incubating mononuclear cells isolated from leukapheresis obtained at Wks 0, 2, and 4 with PA2024 (a recombinant fusion protein comprising prostatic acid phosphatase and GM-CSF) ex vivo for 2 days, after which washed cells were infused. 512 subjects were randomized to sipuleucel-T or placebo (2:1). As part of product characterization efforts, fresh pre- and post-culture (final product - FP) T cells were evaluated in sipuleucel-T products by flow cytometry. The culture supernatant was evaluated for the production of APC and T cell activation-associated cytokines by multiplex luminex assay. Results. APC activation as measured by CD54 upregulation increased from Wk 0 to Wk 2 (P < 0.001) and persisted at the third dose (P < 0.001, Wk 0 vs Wk 4). An analysis of the culture supernatant at each week showed increases in both APC activation-associated cytokines (IL-1α, IL-1β, IL-10, IL-12p70, IL-23, IFNγ, and TNFα) and T cell activation-associated cytokines (IL-2, IL-4, IL-5, IL-10, IL-17, IFNγ, and TNFα). CD134 (OX40), CD137 (4-1BB), CD278 (ICOS), and CD279 (PD-1) expression increased in both CD4+ and CD8+ T cells at Wk 2, with expression diminished at Wk 4. Conclusion. Following The Wk 0 dose, sipuleucel-T products demonstrate evidence of increased APC and T cell activation markers as well as production of T cell activation-associated cytokines. These data provide strong evidence that sipuleucel-T activates APCs ex vivo and facilitates in vivo and ex vivo priming of T cells. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 5608.

Defining Event Reporting In The Cell Processing Facility (CPF)

Defining Event Reporting In The Cell Processing Facility (CPF)

A novel assay for influenza virus quantification using surface plasmon resonance

Quantification of hemagglutinin (HA) by single-radial immuno diffusion (SRID) is the predominant method to ensure product potency in seasonal influenza vaccines. Here a new method for quantification of influenza virus using biosensor technology is presented. The method employs quantification of virus via an inhibition assay format using HA proteins for H1N1, H3N2 and B immobilized on a sensor chip. Initial results showed the assay to have higher sensitivity (detection range 0.5–10 μg/ml), higher precision and significantly lower analysis and hands on time compared with SRID.

Fusion production of solid dispersions containing a heat-sensitive active ingredient by hot melt extrusion and Kinetisol® dispersing

Many techniques for the production of solid dispersions rely on elevated temperatures and prolonged material residence times, which can result in decomposition of temperature-sensitive components. In this study, hydrocortisone was used as a model temperature-sensitive active ingredient to study the effect of formulation and processing techniques as well as to characterize the benefits of KinetiSol® Dispersing for the production of solid dispersions. Preformulation studies were conducted using differential scanning calorimetry and hot stage microscopy to identify optimum carriers for the production of amorphous solid dispersions. After identification, solid dispersions were prepared by hot melt extrusion and KinetiSol® Dispersing, with material characterized by X-ray diffraction, dissolution and potency testing to evaluate physicochemical properties. Results from the preformulation studies showed that vinylacetate:vinylpyrrolidone (PVPVA) copolymer allowed for hydrocortisone dissolution within the carrier at temperatures as low as 160 °C, while hydroxypropyl methylcellulose required temperatures upward of 180 °C to facilitate solubilization. Low substituted hydroxypropyl cellulose, a high glass transition temperature control, showed that the material was unable to solubilize hydrocortisone. Manufacturing process control studies using hot melt extruded compositions of hydrocortisone and PVPVA showed that increased temperatures and residence times negatively impacted product potency due to decomposition. Using KinetiSol® Dispersing to reduce residence time and to facilitate lower temperature processing, it was possible to produce solid dispersions with improved product potency. This study clearly demonstrated the importance of carrier selection to facilitate lower temperature processing, as well as the effect of residence time on product potency. Furthermore, KinetiSol® Dispersing provided significant advantages over hot melt extrusion due to the reduced residence times and lower required processing temperatures. This allowed for the production of solid dispersions with enhanced product potency.

Integrated data from 2 randomized, double‐blind, placebo‐controlled, phase 3 trials of active cellular immunotherapy with sipuleucel‐T in advanced prostate cancer

Sipuleucel-T is an investigational active cellular immunotherapy product designed to stimulate an immune response against prostate cancer. The safety and efficacy of sipuleucel-T was evaluated in 2 identically designed, randomized, double-blind, placebo-controlled trials (D9901 and D9902A) conducted in men with advanced prostate cancer. A total of 225 patients were randomized in D9901 or D9902A to sipuleucel-T (n = 147) or placebo (n = 78), given as 3 intravenous infusions approximately 2 weeks apart. Patients were followed for survival until death or a prespecified cutoff of 36 months after randomization. In the integrated analysis of D9901 and D9902A, patients randomized to sipuleucel-T demonstrated a 33% reduction in the risk of death (hazard ratio, 1.50; 95% confidence interval, 1.10-2.05; P = .011; log-rank). The treatment effect remained strong after performing adjustments for imbalances in baseline prognostic factors, poststudy treatment chemotherapy use, and non-prostate cancer-related deaths. Additional support for the activity of sipuleucel-T is provided by the correlation between a measure of the product's potency, CD54 up-regulation, and overall survival. The most common adverse events associated with treatment were chills, pyrexia, headache, asthenia, dyspnea, vomiting, and tremor. These events were primarily grade 1 and 2, with durations of 1 to 2 days. The integrated results of D9901 and D9902A demonstrate a survival benefit for patients treated with sipuleucel-T compared with those treated with placebo. The generally modest toxicity profile, coupled with the survival benefit, suggests a favorable risk-benefit ratio for sipuleucel-T in patients with advanced prostate cancer.

Development of a Murine Mycobacterial Growth Inhibition Assay for Evaluating Vaccines againstMycobacterium tuberculosis

The development and characterization of new tuberculosis (TB) vaccines has been impeded by the lack of reproducible and reliable in vitro assays for measuring vaccine activity. In this study, we developed a murine in vitro mycobacterial growth inhibition assay for evaluating TB vaccines that directly assesses the capacity of immune splenocytes to control the growth of Mycobacterium tuberculosis within infected macrophages. Using this in vitro assay, protective immune responses induced by immunization with five different types of TB vaccine preparations (Mycobacterium bovis BCG, an attenuated M. tuberculosis mutant strain, a DNA vaccine, a modified vaccinia virus strain Ankara [MVA] construct expressing four TB antigens, and a TB fusion protein formulated in adjuvant) can be detected. Importantly, the levels of vaccine-induced mycobacterial growth-inhibitory responses seen in vitro after 1 week of coculture correlated with the protective immune responses detected in vivo at 28 days postchallenge in a mouse model of pulmonary tuberculosis. In addition, similar patterns of cytokine expression were evoked at day 7 of the in vitro culture by immune splenocytes taken from animals immunized with the different TB vaccines. Among the consistently upregulated cytokines detected in the immune cocultures are gamma interferon, growth differentiation factor 15, interleukin-21 (IL-21), IL-27, and tumor necrosis factor alpha. Overall, we have developed an in vitro functional assay that may be useful for screening and comparing new TB vaccine preparations, investigating vaccine-induced protective mechanisms, and assessing manufacturing issues, including product potency and stability.

Synopsis of the Food and Drug Administration–National Institute of Standards and Technology Co-Sponsored “In VitroAnalyses of Cell/Scaffold Products” Workshop

Complex, dynamic mixtures of cells and structural components, known as cell=scaffold products, are in development as therapeutics for the repair, replacement, and regeneration of a wide variety of tissues damaged by acute, chronic, degenerative, or congenital diseases. These types of tissue-engineered products hold the potential to treat many diseases and injuries that currently do not have effective treatments. Cell=scaffold products are manufactured using complex regimens of cell expansion, materials processing, and cell–biomaterial integration. A critical step toward commercial availability of cell=scaffold-based therapeutics is the establishment of methods to produce a product that can be manufactured in a consistent and reliable manner. To effectively treat patients’ needs, manufacturing processes must be designed to achieve desired, pre-defined product criteria and characteristics. Product inconsistency may also contribute to clinical studies yielding ambiguous data and hinder market approval by the Food and Drug Administration (FDA). Manufacturing processes will vary between different types of cell=scaffold products, but there may be commonalities in the types of product testing used to evaluate product consistency, safety, and potency. Product developers and the FDA face technological challenges in evaluation of cell=scaffold constructs because these products consist of multiple components that must function together to form the final product. To generate discussion on cell=scaffold product evaluation and to promote the initiation of clinical studies and progression to marketing approval of these products, the FDA and the National Institutes of Standards and Technology (NIST) convened a workshop titled ‘‘In Vitro Analyses of Cell=Scaffold Products’’ (Washington, DC, December 2007). This workshop was designed and organized to meet the following two goals. 1) Identify and discuss what questions should be asked and addressed when evaluating cell=scaffold products in preparation for clinical study. 2) Identify and discuss what test methods are available and what analytical methods and processes should be further researched, developed, and standardized to determine the safety, purity, potency, and consistency of cell=scaffold products.

Improving the cellular pertussis vaccine: Increased potency and consistency

Although Europe, Canada and the US have switched from cellular to acellular pertussis vaccines, most developing countries will continue to use the more cost effective cellular vaccine. Consistency of production however is the typical problem inherent to cellular vaccines. Optimising the production process of cellular pertussis bulk suspensions using product potency as a measure is not possible, since the mandatory animal test to measure potency has little discriminatory power. To circumvent this problem, this study focussed on measuring process parameters related to consistency and potency instead, even though the extent of those relationships could not be quantified. Critical evaluation and modification of individual process steps lead to 2 optimised production processes, NVP-96 and NVP-THIJS. These were compared to the original NVP production process in terms of antigen and biomass content, potency, toxicity and immunogenicity in mice. The batch to batch variation for both optimised products was clearly less than the original product for all parameters tested. The biomass content of the NVP-THIJS product was 15% lower than that of the NVP-96 product, while the immunogenicity in mice was twofold to threefold higher. The stability of the NVP-THIJS product remained higher than the NVP-96 product over a period of 2 years, while the decline of the potency of both suspensions was comparable.

Administration of Drug and Nutritional Components in Nano-Engineered Form to Increase Delivery Ratio and Reduce Current Inefficient Practice

The article critically discusses parenteral delivery of self-assembled lipid or amphiphile nanoparticles, in the form of aggregated clusters or particles (capsules). The end-product or drug form is for application by administration of the medicine active in encapsulated form. This is used for site-specific cell manipulation and clinical therapy and introduces this directly to the body via the systemic route. The technology discussed represents a platform formulation that can be modified for a range of specific cellular targets. The components of the nanoparticle are assembled piece-by-piece and this provides an element of design flexibility, with the core particle being built-up in a succession of layers to ensure circulatory longevity and storage stability. This strategy excludes a more generalised delivery and widespread lack of active targeting and thus low dosage rather than avoidance of target, which is at best detrimental and at worst catastrophic in terms of non-targeted cell death. However, in some cases such as the AmBisome nanoparticle this drug delivery approach can work. This "better focussing" is achieved by a dual use of i) biocompatible particle coating chemistry and a ii) cell-ligand imprinted nanoparticle surface that furnishes the engineered nanoparticle with a recognition element to form a complex but more efficacious dispersible fusogenic pro-drug moiety. Non-targeted delivery of drugs such as those commonly forming the basis of transdermal delivery have been generically based on topical or adhesive patch-based delivery (emulsions) systems. This procedure even with recent advancements and patents is customarily inefficient in dosage and payload delivery, inconsistent in terms of product potency and inflexible to further modification or purpose-related enhancement. The assembly and delivery methodologies discussed here take the new experimental medicine and review them in a more focused and purposeful therapy-constructed manner. It is the use of a smart platform technology that is responsible for increased efficacy when applied to the disorder of interest.

Regulations and procedures in parasite vaccine development

Although immunisation protocols for a wide variety of parasitic diseases have been developed, it is often questioned why these do not always reach the market. In this review information about the regulations and procedures that apply to licensing the production and marketing of medicinal preparations, especially parasite vaccines, is presented. These general regulations specify issues on product (quality, safety, efficacy and potency) and production (facilities and consistency). Vaccine developers and manufacturers have to comply with these regulations, which may involve years of research and development. Moreover, where the manufacturer claims specific features of the product, these claims have to be corroborated by (experimental) data. A series of principles has been used to develop vaccines against parasite infections varying from the use of (attenuated) live vaccines to killed vaccines and subunit vaccines. The implications of some specific regulatory issues associated with these approaches are discussed.

Thermogravimetry and vapor pressure moisture

Thermogravimetry (TG), thermogravimetry/mass spectrometry (TG/MS), and loss-on-drying methodology are used to provide residual moisture results for freeze-dried biological products regulated by the US Food and Drug Administration. Residual moisture specifications must be met in order to ensure freeze-dried biological product potency and stability throughout the licensed product's shelf life. TG, TG/MS, loss-on-drying and vapor pressure moisture measurements are compared for a BCG Vaccine. Comparisons are made between residual moisture data for the freeze-dried cake and vapor pressure moisture determinations in the space above the freeze-dried cake in the final container. Vapor pressure moisture precision data is presented for α-interferon and BCG vaccine. Impact of residual moisture and vapor pressure moisture upon product stability is presented.

A review of osteoinductive testing methods and sterilization processes for demineralized bone

Allogeneic demineralized bone has been used extensively as a clinical graft material because it has osteoinductive and osteoconductive properties. Concerns over processing and terminal sterilization procedures that may reduce performance have led clinicians to call for assurances of product potency. There is extensive experience on effects of demineralized bone in animal and cell culture models with the possibility for future evidence-based standards for release of products. Evaluation of the current state of knowledge leads to the fact that we cannot conclude that performance of different lots of demineralized bone allografts in in vivo or in vitro test systems can be used as a measure of clinical performance. It may be possible to adopt an osteoinductivity standard for release-to-market, but it should be followed by clinical monitoring and further research.