Binding interactions with sevelamer and polystyrene sulfonate in vitro

This study explored the binding of 28 drugs, which were selected based on frequency of concomitant use and chemical properties, to sevelamer and polystyrene sulfonate in vitro. The relative binding was determined by dissolving the investigated drugs alone (=control), together with 800 mg of sevelamer and 15 g of polystyrene sulfonate at different pH levels (1.5, 5.5, and 7.4), respectively. After incubation at 37℃ and shaking for 60 min, the solutions were diluted and centrifuged, and the drug concentrations were quantified with validated analytical assays. The binding assays were performed in threefold. The mean relative binding (MRB) at each pH level was calculated, with a MRB >20% for at least one pH level to be considered as relevant binding. Fourteen and 23 potentially new binding interactions were identified with sevelamer and polystyrene sulfonate, respectively. These potentially new binding interactions have to be studied in vivo to assess their clinical relevance

Total body topical 5-fluorouracil for extensive non-melanoma skin cancer

Background Topical 5-fluorouracil 5% cream is one of the treatment modalities for non-melanoma skin cancer (NMSC). There is a lack of suitable therapies to treat patients with extensive NMSC. In this paper we report two patients with extensive NMSC treated by total body application of topical 5-fluorouracil 5% cream. Observations Topical 5-fluorouracil 5% cream was applied twice daily to the total body, including normal appearing skin. During the treatment, weekly blood samples were taken for measurement of 5-fluorouracil levels. All samples showed a 5-fluorouracil level less than the detection level of 10 mu g/l. Total body 5-fluorouracil 5% cream was shown to be an effective treatment in our patients; the majority of lesions cleared in both patients. Conclusions In conclusion, total body topical 5-fluorouracil 5% cream application was successful in two patients with extensive NMSC. No detectable serum level of 5-fluorouracil could be determined. Pain and secondary infections were important side effects in our patients. However, in patients with extensive NMSC this treatment may be considered

A Systematic Evaluation of Cost-Saving Dosing Regimens for Therapeutic Antibodies and Antibody-Drug Conjugates for the Treatment of Lung Cancer

Background: Expensive novel anticancer drugs put a serious strain on healthcare budgets, and the associated drug expenses limit access to life-saving treatments worldwide. Objective: We aimed to develop alternative dosing regimens to reduce drug expenses. Methods: We developed alternative dosing regimens for the following monoclonal antibodies used for the treatment of lung cancer: amivantamab, atezolizumab, bevacizumab, durvalumab, ipilimumab, nivolumab, pembrolizumab, and ramucirumab; and for the antibody-drug conjugate trastuzumab deruxtecan. The alternative dosing regimens were developed by means of modeling and simulation based on the population pharmacokinetic models developed by the license holders. They were based on weight bands and the administration of complete vials to limit drug wastage. The resulting dosing regimens were developed to comply with criteria used by regulatory authorities for in silico dose development. Results: We found that alternative dosing regimens could result in cost savings that range from 11 to 28%, and lead to equivalent pharmacokinetic exposure with no relevant increases in variability in exposure. Conclusions: Dosing regimens based on weight bands and the use of complete vials to reduce drug wastage result in less expenses while maintaining equivalent exposure. The level of evidence of our proposal is the same as accepted by regulatory authorities for the approval of alternative dosing regimens of other monoclonal antibodies in oncology. The proposed alternative dosing regimens can, therefore, be directly implemented in clinical practice.</p

Differences in Evidentiary Requirements Between European Medicines Agency and European Health Technology Assessment of Oncology Drugs—Can Alignment Be Enhanced?

Objectives: National health technology assessments (HTAs) across Europe show differences in evidentiary requirements from assessments by the European Medicines Agency (EMA), affecting time to patient access for drugs after marketing authorization. This article analyzes the differences between EMA and HTA bodies’ evidentiary requirements for oncology drugs and provides recommendations on potential further alignment to minimize and optimally manage the remaining differences. Methods: Interviews were performed with representatives and drug assessment experts from EMA and HTA bodies to identify evidentiary requirements for several subdomains and collect recommendations for potentially more efficiently addressing differences. A comparative analysis of acceptability of the evidence by EMA and the HTA bodies and for potential further alignment between both authorities was conducted. Results: Acceptability of available evidence was higher for EMA than HTA bodies. HTA bodies and EMA were aligned on evidentiary requirements in most cases. The subdomains showing notable differences concerned the acceptance of limitation of the target population and extrapolation of target populations, progression-free survival and (other) surrogate endpoints as outcomes, cross-over designs, short trial duration, and clinical relevance of the effect size. Recommendations for reducing or optimally managing differences included joint early dialogues, joint relative effectiveness assessments, and the use of managed entry agreements. Conclusions: Differences between assessments of EMA and HTA bodies were identified in important areas of evidentiary requirements. Increased alignment between EMA and HTA bodies is suggested and recommendations for realization are discussed

Differences in evidentiary requirements for oncology drug effectiveness assessments among six European health technology assessment bodies:can alignment be improved?

Objectives: Evidentiary requirements for relative effectiveness assessment vary among European health technology assessment (HTA) bodies, affecting the time to HTA decision-making and potentially delaying time to patient access. Improved alignment may reduce this time; therefore, we aim to analyze the differences in evidentiary requirements for oncology drug assessments among European HTA bodies and provide recommendations toward an increased alignment. Methods: Interviews were conducted with stakeholders in drug assessments of Italy, the Netherlands, Poland, Portugal, England and Wales, and Sweden about evidentiary requirements for several subdomains to identify differences and obtain recommendations for addressing differences. The interview results were analyzed on degrees of evidence acceptability per HTA body and alignment on evidentiary requirements among HTA bodies. Results: Subdomains demonstrating noteworthy differences concerned the acceptability of extrapolation to other populations, class effects, progression-free survival and (other) surrogate endpoints as outcomes, the absence of quality-of-life data, single-arm trials, cross-over trial designs, short trial duration, and the clinical relevance of effect size. Conclusion: Alignment can be enhanced to reduce time to decision-making and to improve equity in patient access. Proposed recommendations to achieve this included joint early dialogues, intensified collaboration and exchange between countries, joint relative effectiveness assessments, and the use of access agreements.</p

Clinical implications of germline variations for treatment outcome and drug resistance for small molecule kinase inhibitors in patients with non-small cell lung cancer

Small-molecule kinase inhibitors (SMKIs) represent the cornerstone in the treatment of non-small cell lung cancer (NSCLC) patients harboring genetic driver mutations. Because of the introduction of SMKIs in the last decades, treatment outcomes have drastically improved. Their treatment efficacy, the development of drug resistance as well as untoward toxicity, all suffer from large patient variability. This variability can be explained, at least in part, by their oral route of administration, which leads to a large inter- and intra-patient variation in bioavailability based on differences in absorption. Additionally, drug-drug and food-drug interactions are frequently reported. These interactions could modulate SMKI efficacy and/or untoward toxicity. Furthermore, the large patient variability could be explained by the presence of germline variations in target receptor domains, metabolizing enzymes, and drug efflux transporters. Knowledge about these predictor variations is crucial for handling SMKIs in clinical practice, and for selecting the most optimal therapy. In the current review, the literature search included all SMKIs registered for locally-advanced and metastatic NSCLC by the US Food and Drug Administration (FDA) or European Medicines Agency (EMA) until March 24th, 2022. The BIM deletion showed a significantly decreased PFS and OS for East-Asian patients treated with gefitinib, and has the potential to be clinically relevant for other SMKIs as well. Furthermore, we expect most relevance from the ABCG2 34 G>A and CYP1A1 variations during erlotinib and gefitinib treatment. Pre-emptive CYP2D6 testing before starting gefitinib treatment can also be considered to prevent severe drug-related toxicity. These and other germline variations are summarized and discussed, in order to provide clear recommendations for clinical practice

Evidence- and consensus-based guidelines for drug-drug interactions with anticancer drugs; A practical and universal tool for management

Drug-drug interactions (DDIs) with anticancer drugs are common and can significantly affect efficacy and toxicity of treatment. Therefore, a Dutch Multidisciplinary Expert group is assessing the clinical significance of DDIs in oncology and provides recommendations for the management of these DDIs. We present an overview of methodology and outcome of an evidence- and consensus-based assessment of DDIs between anticancer drugs and non-anticancer drugs. A literature search was performed through PubMed and EMA and FDA assessment reports, to identify potential DDI's involving anticancer drugs. For each potential DDI a concept report for risk analysis and practical advice for management was created. Subsequently, this risk analysis and the corresponding advice were assessed and weighed. A total of 290 potential DDIs have been identified in the literature thus far. Of these 290 potential DDIs, the Expert Group has identified 94 (32%) DDIs as clinically relevant, with a need for an automated alert and a suggested intervention. Furthermore, 110 DDIs have been identified as clinically not relevant. For 86 potential DDIs evidence supporting a relevant DDI was insufficient and in these cases neither an alert nor advice regarding a suggested intervention were formulated. A transparent risk analysis is presented for identification of clinically relevant DDIs with anticancer drugs. Integration of DDI guidelines into the national electronic prescribing system is essential to achieve optimal efficacy and minimal toxicity in patients receiving anticancer therapy. A clear overview of clinically relevant DDIs with anticancer therapy provides clinicians with a structured, evidence-based and consensus-built tool for anticancer therapy surveillance

Lean Body Mass and Total Body Weight Versus Body Surface Area as a Determinant of Docetaxel Pharmacokinetics and Toxicity

Aim:This study examined whether anthropometric and body composition parameters such as body surface area (BSA), lean body mass (LBM), and total body weight (TBW) are correlated with docetaxel clearance and exposure by analyzing area under the curve. In addition, LBM, TBW, and a fixed dose were compared with BSA as dosing parameters for dose individualization of docetaxel.Methods:Thirty-six patients receiving docetaxel chemotherapy for breast or metastatic castration-resistant prostate carcinoma were included. Before treatment, LBM was measured using a dual-energy X-ray absorptiometry scanner. Blood samples were collected up to 180 minutes after dosing to analyze docetaxel concentrations and determine individual pharmacokinetic parameters.Results:No significant correlations were found between docetaxel clearance and the anthropometric and body composition variables (BSA, LBM, and TBW). The area under the curve was significantly but poorly correlated with BSA [r = 0.452 (P = 0.016)] and TBW [r = 0.476 (P = 0.011)]. The mean absolute percentage error and mean error of simulated dosing based on LBM and fixed dosing were not significantly different from those of BSA. For TBW, only mean absolute percentage error was significantly higher compared with dosing based on BSA (24.1 versus 17.1, P = 0.001).Conclusions:There was no clinically relevant correlation between docetaxel pharmacokinetics and the anthropometric and body composition variables BSA, LBM, and TBW. Therefore, dose individualization of docetaxel based on LBM, TBW, or fixed dosing cannot be recommended over BSA-based dosing