Use of tyrosine kinase inhibitors for chronic myeloid leukemia: management of patients and practical applications for pharmacy practitioners

Enhanced Bioavailability and Reduced Variability of Dasatinib and Sorafenib with a Novel Amorphous Solid Dispersion Technology Platform

Despite clinical advances with protein kinase inhibitors (PKIs), oral administration of many PKIs is associated with highly variable plasma exposure and a narrow therapeutic window. We developed a novel hybrid nanoparticle-amorphous solid dispersion (ASD) technology platform consisting of an amorphous PKI embedded in a polymer matrix. The technology was used to manufacture immediate-release formulations of 2 tyrosine kinase inhibitors (TKIs), dasatinib and sorafenib. Our primary objective was to improve the absorption properties and reduce the pharmacokinetic (PK) variability of each TKI. The PKs of XS004 (dasatinib-ASD, 100 mg tablet) and XS005 (sorafenib-ASD, 2 × 50 mg capsules) were compared with their crystalline formulated reference drugs (140 mg of dasatinib-reference and 200 mg of sorafenib-reference). The in vitro biopharmaceutics of dasatinib-ASD and XS005-granulate showed sustained increased solubility in the pH range 1.2-8.0 compared to their crystalline references. In vivo, XS004 was bioequivalent at a 30% lower dose and showed increased absorption and bioavailability, with 2.1-4.8 times lower intra- and intersubject variability compared to the reference. XS005 had an increased absorption and bioavailability of 45% and 2.2-2.8 times lower variability, respectively, but it was not bioequivalent at the investigated dose level. Taken together, the formulation platform is suited to generate improved PKI formulations with consistent bioavailability and a reduced pH-dependent absorption process.

Acceptability of pharmacist-led interventions to resolve drug-related problems in patients with chronic myeloid leukaemia

PURPOSE

Chronic myeloid leukaemia (CML) patients on long-term tyrosine kinase inhibitor (TKI) therapy are susceptible to drug-related problems (DRPs). This study aimed to evaluate the acceptability and outcomes of pharmacist-led interventions on DRPs encountered by CML patients.

METHODS

This study included participants from the intervention arm of a randomised controlled trial which was conducted to evaluate the effects of pharmacist-led interventions on CML patients treated with TKIs. Participants were recruited and followed up in the haematology clinics of two hospitals in Malaysia from March 2017 to January 2019. A pharmacist identified DRPs and helped to resolve them. Patients were followed-up for six months, and their DRPs were assessed based on the Pharmaceutical Care Network Europe Classification for DRP v7.0. The identified DRPs, the pharmacist's interventions, and the acceptance and outcomes of the interventions were recorded. A Poisson multivariable regression model was used to analyse factors associated with the number of identified DRPs per participant.

RESULTS

A total of 198 DRPs were identified from 65 CML patients. The median number of DRPs per participants was 3 (interquartile range: 2, 4). Most participants (97%) had at least one DRP, which included adverse drug events (45.5%), treatment ineffectiveness (31.5%) and patients' treatment concerns or dissatisfaction (23%). The 228 causes of DRPs identified comprised the following: lack of disease or treatment information, or outcome monitoring (47.8%), inappropriate drug use processes (23.2%), inappropriate patient behaviour (19.9%), suboptimal drug selection (6.1%), suboptimal dose selection (2.6%) and logistic issues in dispensing (0.4%). The number of concomitant medications was significantly associated with the number of DRPs (adjusted Odds Ratio: 1.100; 95% CI: 1.005, 1.205; p = 0.040). Overall, 233 interventions were made. These included providing patient education on disease states or TKI-related side effects (75.1%) and recommending appropriate instructions for taking medications (7.7%). Of the 233 interventions, 94.4% were accepted and 83.7% were implemented by the prescriber or patient. A total of 154 DRPs (77.3%) were resolved.

CONCLUSIONS

The pharmacist-led interventions among CML patients managed to identify various DRPs, were well accepted by both TKI prescribers and patients, and had a high success rate of resolving the DRPs.

Front-line use of tyrosine kinase inhibitors in chronic phase chronic myeloid leukemia: Practice considerations

The development of BCR-ABL-targeting tyrosine kinase inhibitors has transformed chronic phase chronic myeloid leukemia (CP CML) from a disease with a terminal prognosis to a treatable chronic illness. Long-term treatment with tyrosine kinase inhibitors means that patients have to be clinically managed and monitored over extended periods of time, thus a patient-centered, medically integrated, and multidisciplinary oncology healthcare team is required to support patients through their journey. Pharmacists work with patients, physicians, and the wider support team to select the optimum therapy plan for a given patient. These decisions are based on risk factors, comorbidities, concomitant medications, and personal circumstances and pharmacists advise on the efficacy and safety of different treatment options. Additionally, pharmacists are a key point-of-contact and resource for monitoring patient response to treatment, identifying and managing adverse events and drug-drug interactions, any subsequent therapy plan modifications, and, potentially, treatment-free remission. Pharmacists also assist with patient education, medication adherence, and financial discussions with patients throughout the long course of the disease. This review provides an overview of BCR-ABL tyrosine kinase inhibitors, discusses the role of the medically integrated pharmacy team, and suggests strategies that pharmacists can use in patient management and clinical decision-making to optimize the treatment of CP CML.

Safe handling of oral antineoplastic medications: Focus on targeted therapeutics in the home setting

Introduction With the growing number of oral targeted therapies being approved for use in cancer therapy, the potential for long-term administration of these drugs to cancer patients is expanding. The use of these drugs in the home setting has the potential to expose family members and caregivers to them either through direct contact with the drugs or indirectly by exposure to the parent compounds and/or their active metabolites in contaminated patients' waste. Methods A systematic literature review was performed and the known adverse health effect of 32 oral targeted therapeutics is summarized. In particular, the carcinogenicity, genotoxicity, and embryo-fetal toxicity, along with the route of excretion were evaluated. Results Carcinogenicity testing has not been performed on most of the oral targeted therapeutics and the genotoxicity data are mixed. However, the majority of these drugs exhibit adverse reproductive effects, some of which are severe. Currently, available data does not permit the possibility of a health hazard from inappropriate handling of drugs and contaminated patients waste to be ignored, especially in a long-term home setting. Further research is needed to understand these issues. Conclusions With the expanding use of targeted therapies in the home setting, family members and caregivers, especially those of reproductive risk age, are, potentially at risk. Overall basic education and related precautions should be taken to protect family members and caregivers from indirect or direct exposure from these drugs. Further investigations and discussion on this subject are warranted.

Bosutinib Therapy in Patients With Chronic Myeloid Leukemia: Practical Considerations for Management of Side Effects

The past decade has witnessed great advances in the treatment of chronic myeloid leukemia (CML), brought about in large part by the development of BCR-ABL tyrosine kinase inhibitors (TKIs). Bosutinib joins the armamentarium of approved TKIs for the treatment of chronic phase (CP), accelerated phase (AP), and blast phase (BP) Philadelphia chromosome (Ph)-positive CML resistant to or intolerant of prior therapy. Bosutinib has an adverse-event (AE) profile distinct from that of other TKIs. Diarrhea is the predominant toxicity associated with bosutinib treatment; other commonly reported nonhematologic AEs include rash and liver enzyme elevations. Cardiac events, fluid retention, and electrolyte abnormalities are infrequent. Optimal response to bosutinib requires adherence, which depends, in part, upon optimal management of associated toxicities. The oncology clinician can facilitate this process by providing patient education, timely patient follow-up, and close monitoring to promptly identify and manage AEs. Thus, optimal patient management requires a thorough and current understanding of toxicity profiles and AE management paradigms. This review provides an overview of bosutinib safety data derived from ongoing clinical trials and offers practical clinical strategies currently used to manage toxicities associated with bosutinib treatment in patients with Ph-positive CP, AP, and BP CML.

13-Oxyingenol dodecanoate, a cytotoxic ingenol derivative, induces mitochondrial apoptosis and caspase-dependent Akt decrease in K562 cells

13-Oxyingenol dodecanoate (13OD) is an ingenol derivative prepared from Chinese traditional medicine Euphorbia kansui without any report about its bioactivity. The present study demonstrated for the first time that 13OD displayed potent cytotoxicity against chronic myeloid leukemia K562 cells in vitro. 13OD inhibited proliferation, induced G2/M phase arrest, and exhibited potent apoptotic activity in K562 cells. In K562 cells, 13OD disrupted the mitochondrial membrane potential and induced high level of ROS, which played an indispensable role in 13OD-induced apoptosis. Further investigations on the molecular mechanisms revealed that total Akt protein level was decreased in a caspase-dependent way after treatment with 13OD; in addition, ERK was activated by 13OD, and this activation played a protective role in 13OD stimulation. Altogether, these results revealed that the cytotoxic ingenol derivative 13OD induced apoptosis with novel mechanisms for the proapoptotic function in cancer cells, and suggested that 13OD may serve as a lead template for rational drug design and for future anticancer agent development.

Cytotoxicity of the compounds isolated from Pulsatilla chinensis saponins and apoptosis induced by 23-hydroxybetulinic acid

CONTEXT

The rizoma of Pulsatilla chinensis (Bunge) Regel has been used as a traditional Chinese medicinal herb for thousands of years. Total saponins from P. chinensis can induce the apoptosis of solid cancer cells; however, their activity on chronic myeloid leukemia and the mechanisms remains unknown.

OBJECTIVE

To study the activity of total saponins and the main active fractions from P. chinensis saponins on chronic myeloid leukemia, and to illustrate the mechanisms underlying the anticancer activities.

MATERIALS AND METHODS

The cytotoxic activity were assayed by MTT; cell cycle arrest and apoptosis were tested by flow cytometry system; changes in the mitochondrial membrane potential were determined using JC-1; and the apoptosis signaling pathway was determined by western blotting.

RESULTS

We demonstrated that total P. chinensis saponin displayed cytotoxic activity against K562 cell line. In addition, we identified 23-hydroxybetulinic acid (HBA), pulchinenoside A (PA), and anemoside B4 (AB4) from the total saponins, with the most cytotoxic compound HBA. Glycosylation at C3 and C28 of HBA significantly reduces its cytotoxicity. HBA could promote cell cycle arrest at S phase and induce apoptosis via intrinsic pathway. HBA disrupts mitochondrial membrane potential significantly (p < 0.01) and selectively downregulates the levels of Bcl-2, survivin and upregulates Bax, cytochrome C, cleaved caspase-9 and -3.

DISCUSSION AND CONCLUSION

Total saponins from P. chinensis may be effective natural products against human chronic myelogenous leukemia; HBA is one of the bioactive components responsible for its anticancer activity, and could be further investigated as an alternative therapeutic drug for leukemia.