Updates in the Treatment of Non-Metastatic Castrate-Resistant Prostate Cancer: The Benefit of Second-Generation Androgen Receptor Antagonists

OBJECTIVE

To review pharmacology, efficacy, safety, and considerations for use, of second-generation androgen receptor (AR) antagonists in treatment of nonmetastatic castrate-resistant prostate cancer (M0CRPC).

DATA SOURCES

Conducted search in PubMed and Google scholar (January, 1, 2002-December 31, 2022), using relevant terms.

STUDY SELECTION AND DATA EXTRACTION

Relevant English-language studies, conducted in humans evaluating second-generation AR antagonists for M0CRPC, and additional articles and package inserts were considered.

DATA SYNTHESIS

Apalutamide, darolutamide, and enzalutamide are effective in delaying the time to development of metastatic prostate cancer in men with M0CRPC with a rapid prostate-specific antigen (PSA) doubling time (<10 months). No head-to-head, randomized, clinical trials have been conducted. The most common adverse effects include fatigue and hypertension, and quality of life is maintained in most patients. Cost is similar among the agents (~$15,000/month). Drug-drug interactions vary among these agents and should be considered, when selecting therapy as well as likely adherence. Darolutamide is administered twice daily with the others once daily.

RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE

Second-generation AR antagonists are effective in reducing time to development of metastatic disease and prolonging overall survival in patients with M0CRPC and a PSA doubling time of <10 months. Recent imaging advances may alter how we evaluate outcomes.

CONCLUSIONS

Second-generation AR antagonists improve disease control and overall survival. Generally, they are well tolerated and QOL is maintained. Selection of the best agent is based on the adverse effect profile, potential for drug- and disease-interactions, administration, cost, and patient preference.

Expansion of MyDispense: A Descriptive Report of Simulation Activities and Assessment in a Certified Pharmacy Technician Training Program

BACKGROUND

Yale New Haven Health (YNHH) implemented a pharmacy technician training program in 2016. The curriculum includes 14 weeks of combined didactic and simulation hours (280 h in total), followed by 360 h of experiential learning. MyDispense, an online pharmacy simulation, allows students to develop and practice their dispensing skills in a safe environment with minimal consequences for mistakes. We describe a novel innovation, expanding the functionality of MyDispense to the training of pharmacy technicians.

METHODS

Technician training coordinator, supervisor, faculty members with experience in MyDispense, and experiential pharmacy students created cases within the MyDispense software that were targeted towards pharmacy technician activities. Activities were aligned with current American Society of Health-System Pharmacists (ASHP)-Accreditation Council for Pharmacy Education (ACPE) Accreditation Standards for pharmacy technician education and training programs.

RESULTS

A total of 14 cases were developed to be utilized in student technician training, and account for approximately 14 h of simulation.

CONCLUSIONS

MyDispense is an innovative software that could allow students to access and complete exercises, and to continue developing dispensing skills in a safe, remote environment. We identified similarities between activities performed by student pharmacists and student pharmacy technicians, expanding MyDispense to a new learner group to practice, develop and be assessed on dispensing skills within their scope, as part of a formal technician training program and in preparation for the Pharmacy Technician Certification Examination (PTCE).

International Society of Oncology Pharmacy Practitioners (ISOPP) position statement: Role of the oncology pharmacy team in cancer care

The Oncology Pharmacy Team (OPT), consisting of specialty-trained pharmacists and/or pharmacy technicians, is an integral component of the multidisciplinary healthcare team (MHT) involved with all aspects of cancer patient care. The OPT fosters quality patient care, safety, and local regulatory compliance. The International Society of Oncology Pharmacy Practitioners (ISOPP) developed this position statement to provide guidance on five key areas: 1) oncology pharmacy practice as a pharmacy specialty; 2) contributions to patient care; 3) oncology pharmacy practice management; 4) education and training; and 5) contributions to oncology research and quality initiatives to involve the OPT. This position statement advocates that: 1) the OPT be fully incorporated into the MHT to optimize patient care; 2) educational and healthcare institutions develop programs to continually educate OPT members; and 3) regulatory authorities develop certification programs to recognize the unique contributions of the OPT in cancer patient care.

Integration of a Virtual Dispensing Simulator "MyDispense" in an Experiential Education Program to Prepare Students for Community Introductory Pharmacy Practice Experience

BACKGROUND

Technology is increasingly used to enhance pharmacy education. We sought to evaluate student learning and preparedness for community introductory pharmacy practice experiences (IPPEs) after implementation of "MyDispense" into experiential education.

METHODS

Both first-year pharmacy students and assigned community IPPE preceptors were eligible. Students were stratified based on previous community pharmacy experience (< or ≥ 50 h), then randomized to complete MyDispense exercises before IPPE (group A) or after 24-32 h of IPPE (group B). We evaluated preceptors' assessment of student readiness using a 6-item Likert scale survey and students' readiness and opinion of MyDispense using an anonymous 9-item survey. Descriptive statistics were used to characterize data. The Mann-Whitney U test was used to compare groups and a p-value < 0.05 was considered statistically significant.

RESULTS

Of 177 eligible students, 155 were randomized and 56 completed study. Group A included 32 students; 56.3% had prior community practice experience. Group B included 24 students; 50% had prior community practice experience. Forty-eight preceptors were enrolled. Students who completed exercises before rotation received higher preceptor scores for patient counseling of self-care and of medications (p < 0.05 for both). Students self-assessed their counseling skills lower than all other skills; 30.4% and 42.9% of students felt mostly or always prepared to counsel for self-care and medications, respectively. Students found MyDispense straightforward, realistic, and appreciated the ability to practice in a safe, electronic, community pharmacy, patient-care environment.

CONCLUSION

Simulation-based software, such as MyDispense, can enhance learner understanding of the prescription fill and counseling process in a community pharmacy practice setting.

Use of Cannabis and Cannabinoids in Patients With Cancer

OBJECTIVE

To review pharmacology, available dosage forms, efficacy, and safety of cannabis and cannabinoids in cancer patients.

DATA SOURCES

In PubMed (1965 to June 2020) the search was conducted using the search terms cannabidiol, cannabis, CBD, dronabinol, endocannabinoids, medical marijuana, nabiximols, nabilone, THC, and cancer. Abstracts from article bibliographies were reviewed.

STUDY SELECTION AND DATA EXTRACTION

Relevant English-language studies conducted in humans evaluating cannabis and cannabinoids for cancer treatment or related symptoms were considered. Reference lists in relevant articles, package inserts, guidance documents, and addditional articles evaluating cannabis and cannabinoids were identified.

DATA SYNTHESIS

Cannabis and cannabinoid effectiveness can be attributed to active components delta-9-tetrahydrocannabinol and cannabidiol. Multiple dosage forms exist, each with different properties contributing to efficacy and safety differences. No data supports use as anticancer agents, and mixed efficacy results have been reported when used in cancer patients with nausea, pain, and anorexia. Inclusion of medicinal and synthetic products, small sample sizes, varying patient populations, and different dosage forms, doses, and drug combinations. These products are well tolerated, and adverse effects depend on the main active component.

RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE

Healthcare professionals need to identify appropriateness, monitor, and document use of cannabis and cannabinoids similar to other drug therapies as well as educate the patients/ caregivers about potential benefits and risks.

CONCLUSIONS

Current evidence for use of medical cannabis and cannabinoids in cancer patients is weak. However, healthcare professionals are in an ideal role to monitor and educate patients using medical cannabis and cannabinoids.

The Expanding Role of the Oncology Pharmacist

Although oncology pharmacists have been involved in the care of cancer patients for over 50 years, the role of the oncology pharmacist continues to expand. Initially, pharmacists were primarily based within either an inpatient or outpatient pharmacy setting and their work focused on providing the necessary safety checks to dispense cancer-related medications. With technology freeing up pharmacists from dispensing functions and advanced training in direct patient care (e.g., oncology residency, oncology fellowship), the oncology pharmacist was able to provide direct patient care at the bedside or within the clinic where treatment decisions are made by the healthcare team. In fact, they have become integral members of the healthcare team. This Issue describes several expanding roles of oncology pharmacists in stem cell transplant, hematology, gastrointestinal oncology, and precision genomics, as well as oncology pharmacists preventing a reduction in cancer patient visits as the oncology physician shortage occurs. Oncology pharmacists are an integral part of the cancer care team; their value has been documented in several studies, and is highlighted in this Issue. We encourage the profession to continue to document their value so that one day each patient can have an oncology pharmacist as part of their cancer care team.

Documentation of medical marijuana use in cancer patients

Purpose

Medical marijuana is often used as adjuvant therapy in cancer patients for symptom management, although limited evidence-based studies evaluating its efficacy or safety exist. Similar to over-the-counter medications, supplements, or herbal products, documentation of medical marijuana is important to monitor efficacy, potential adverse effects, or interactions. The objective of this quality improvement study was to improve the consistency of medical marijuana documentation in cancer patients by assessing current practices; educating healthcare team members about the importance of documentation and newly established documentation process; and evaluating the new documentation process.

Methods

This three-part quality improvement study was approved by the Institutional Review Board. In part I, a voluntary survey was sent via email to Cancer Center healthcare personnel to assess the current documentation process of medical marijuana. In part II, a best practice process for documenting medical marijuana in the electronic medical record was established. Medical marijuana was to be listed as a historical medication in the medication list. In-person and electronic education sessions were offered to Cancer Center clinical staff. The education emphasized the importance of documenting medical marijuana use and provided a detailed process for electronic medical record documentation. A pre- and post-test to assess understanding was also included. Part III was a retrospective chart review to evaluate documentation practices of certified medical marijuana users in the Cancer Center. Patients included in the study were greater than 18 years old and certified for medical marijuana use on or after 1 January 2018. Department of Corrections patients were excluded. Descriptive statistics were used for data analysis.

Results

The survey results in part I demonstrated a lack of consistency in the documentation of medical marijuana in the Cancer Center. The pre- and post-test scores measured in part II showed a significant improvement in understanding after education was provided. The average pre-test score was a 61 and post-test score was 88, indicating an average increase of 27 points. A larger increase in test scores was observed in those attending the in-person education than the online sessions ( p < 0.002). The results of the retrospective chart review in part III revealed 56 patients who met inclusion criteria, but only 39 patients were alive and evaluated at the time of the retrospective chart review. Of the 39 patients, 22 never completed the patient registration process and therefore, would never have been able to obtain medical marijuana. Seven patients had medical marijuana properly documented in their medication list and 10 patients were missing documentation in the medication list, showing room for improvement in documentation practices.

Conclusions

This quality improvement study led to the implementation of medical marijuana documentation in the medication list. Education increased healthcare team members understanding of medical marijuana utilization and the importance of documentation.

Demonstrating the value of the oncology pharmacist within the healthcare team

INTRODUCTION

Although many oncology pharmacists are embedded members within the healthcare team, data documenting their contributions to optimal patient outcomes are growing. The purpose of this paper is to demonstrate the value of the oncology pharmacist within the healthcare team and describe the knowledge, skills, and functions of the oncology pharmacist.

METHODS

A systematic literature review of articles that were published on PubMed between January 1951 and October 2018 was completed. Identified abstracts were reviewed and included if they focused on measuring the value or impact of the oncology pharmacist on provider/patient satisfaction, improvement of medication safety, improvement of quality/clinical care outcomes, economics, and intervention acceptance. Review articles, meta-analysis, and studies not evaluating oncology pharmacist activities were excluded. Studies were thematically coded into four themes (clinical care, patient education, informatics, and cost savings) by 10 oncology pharmacists.

RESULTS

Four-hundred twenty-two articles were identified, in which 66 articles met inclusion criteria for this review. The selected literature included 27 interventional and 38 descriptive studies. The value of the oncology pharmacist was demonstrated by published articles in four key themes: clinical care, patient education, informatics, and cost savings.

CONCLUSION

With an expected shortage of oncology physicians and the ongoing development of complex oncology therapies, the board-certified oncology pharmacist is well suited to serve as a physician extender alongside nurse practitioners and/or physician assistants as the medication expert on the oncology care team. The demonstrated value of the oncology pharmacist supports their role as frontline providers of patient care.

Potential role of rituximab in metastatic castrate-resistant prostate cancer

Nearly all men with prostate cancer who are treated with androgen deprivation therapy develop disease progression. There is considerable evidence to suggest that CXCL 13 released by tumor cells leads to B-cell infiltration into the prostate cells. This B-cell infiltration has been postulated to play a role in development of disease progression following androgen-deprivation therapies. We present a case of a patient who achieved remission of metastatic castrate-resistant prostate cancer after receiving rituximab and bendamustine for the treatment of follicular lymphoma. The findings in this report suggest that further investigation is warranted for utilizing B-cell targeted therapy in delaying progression of castrate-resistant prostate cancer.

Subcutaneous metastasis from recurrent basaloid squamous cell carcinoma of the esophagus

Background

Esophageal cancer is the 11th most common cause of cancer mortality in the United States. It is aggressive in nature and has an ability to spread rapidly through direct extension, lymphatic spread, or hematogenously. With an estimated incidence of 1%, cutaneous metastases from esophageal cancer are extremely rare.

Case presentation

In this case study and review, we describe a case of recurrent esophageal basaloid squamous cell carcinoma presenting as multiple, rapidly progressing and tender subcutaneous nodules. A 69-year-old male with history of basaloid squamous cell carcinoma of the esophagus treated with concurrent chemoradiation, presented to his oncologist with complaints of a large, painful nodule at the nape of his neck approximately two years after completing treatment. On further examination, he was noted to have multiple, well circumscribed, solid, tender nodules on his abdominal wall along with a painful nodule on the pulp of his index finger. Histopathology from all sites revealed skin infiltration by high-grade invasive basaloid subtype of squamous cell carcinoma, similar to patient’s prior known and treated primary esophageal cancer. Further imaging work up showed extensive metastatic disease involving lung, liver, and brain.

Conclusion

Esophageal squamous cell carcinoma rarely metastasize to the skin. Subcutaneous nodules can be the first presentation of recurrent disease. The lesions are commonly confused with skin infections and treated inappropriately with antibiotics, leading to delay in diagnosis of recurrent disease. Early biopsy of suspicious lesions should be performed, especially in patients with history of cancer, such that prompt diagnosis and treatment can occur to maximize patient outcomes.

Pharmacists' roles in oncology pharmacy services: Results of a global survey

Background

Oncology pharmacists are capable of providing medication therapy management (MTM) because of their level of training, practice experiences, and responsibilities. Very little data exist about their current practice, including changing roles in the multidisciplinary team, overall impact, and effects in the education of patients and healthcare professionals.

Methods

A 70-item survey about oncology pharmacists' activities in oral chemotherapy programs, MTM, and collaborative practice agreements (CPAs) was deployed using a web survey tool (Qualtrics, Provo, UT, USA), targeting pharmacist members of American College of Clinical Pharmacy (ACCP) Hematology/Oncology Practice and Research Network (PRN). The objective of this study was to determine oncology pharmacists' activities in areas of oral chemotherapy programs, MTM, and CPAs. A cross-sectional survey was distributed to the ACCP Hematology/Oncology PRN membership. Investigational Review Board approval was obtained.

Results

Of the 795 members who were sent the survey, 81 members (10%) responded; 33 respondents (47%) are involved with an oral chemotherapy program; with 42% measuring outcomes of programs. Only six pharmacists (19%) have published or presented their data. A total of 28 (35%) respondents provide MTM services, with almost half (43%) of these MTM services being dictated by CPAs. A small fraction of these pharmacists (21.4%) reported conducting quality assurance evaluations of their MTM services and three pharmacists (10.7%) reported publishing their results. Those pharmacists practicing under CPAs ( n = 28) were surveyed as to activities included in their CPA. The most common activities included adjusting medication, ordering, interpreting, and monitoring lab tests, developing therapeutic plans and educating patients. Reimbursement for providing these services was uncommon: MTM (4%), oral chemotherapy program (6%), and CPA services (11%). Reported obstacles to reimbursement included lack of understanding, administrative assistance, or time with setting up reimbursement models within the institution.

Conclusion

Many oncology pharmacists are participating in oral chemotherapy programs, MTM, and/or CPAs and perceived barriers were identified. Increased efforts should be directed toward prospectively reporting and assessing the impact these services have on patient care.

Impact of a pharmacist-led oral chemotherapy-monitoring program in patients with metastatic castrate-resistant prostate cancer

Background

With the introduction of oral chemotherapy, the paradigm for cancer treatment is shifting. Use of oral chemotherapy agents offers a non-invasive option for patients with metastatic castrate-resistant prostate cancer. However, these medications are not without challenges including strict adherence for optimal effects, novel toxicity profiles, frequent lab parameter monitoring, high cost, and proper handling and disposal methods. Pharmacists are positioned to play a key role in providing patients with the education required to assure an optimal treatment course is carried out.

Methods

Two cohorts of patients receiving abiraterone, bicalutamide, or enzalutamide for metastatic castrate-resistant prostate cancer seen in our outpatient cancer center 21 months before and 24 months after the implementation of a pharmacist-led oral chemotherapy-monitoring program in December of 2012 were retrospectively compared. Patients were evaluated for number of interventions, adherence to lab parameter monitoring, and overall time on each therapy.

Results

Of the 64 patients identified, 31 patients fulfilled inclusion criteria. A significant increase in the average number of interventions per patient (6.9 vs. 2.6; P = 0.004) and adherence to lab parameter monitoring (10 vs. 3; P = 0.04) in the post-program implementation cohort was found. However, no significant difference in overall time on therapy (10.3 vs. 8.1; P = 0.341) between the two groups was observed.

Conclusion

These results suggest a potential opportunity exists to maximize oral chemotherapy treatment outcomes with the addition of a formalized monitoring program directed by an oncology pharmacist.

Ledipasvir-Sofosbuvir: A Once-Daily Oral Treatment Option for Chronic Hepatitis C Virus Genotype 1 Infection

Chronic hepatitis C virus (HCV) genotype 1 historically has been the most difficult to treat HCV genotype, and patients infected with this genotype had been previously treated with interferon-based therapy. In recent years, however, treatment options for chronic HCV infection have rapidly changed to an all-oral regimen. Ledipasvir-sofosbuvir is an oral fixed-dose (ledipasvir 90 mg-sofosbuvir 400 mg) combination of two direct-acting antiviral drugs. Four phase 3 clinical trials (ION-1-4) evaluated ledipasvir-sofosbuvir with and without ribavirin in patients with HCV genotype 1. High rates of sustained virologic response (SVR) occurred with ledipasvir-sofosbuvir alone in treatment-naïve and treatment-experienced patients without cirrhosis as well as in treatment-naïve patients with cirrhosis when administered for 12 weeks. In treatment-experienced patients with cirrhosis, 24 weeks of ledipasvir-sofosbuvir was also highly effective. Furthermore, treatment-naïve patients without cirrhosis (particularly those with HCV RNA serum concentrations < 6 million IU/ml) can achieve a similar SVR with only 8 weeks of therapy. Similarly, in patients coinfected with human immunodeficiency virus and HCV genotype 1 who were treated with ledipasvir-sofosbuvir for 12 weeks, a high SVR was observed in those with and without cirrhosis as well as treatment-naïve and treatment-experienced patients. Ledipasvir-sofosbuvir is well tolerated, with fatigue, headache, nausea, diarrhea, and insomnia being the most common adverse effects, which are typically mild to moderate in nature. This combination antiviral can be taken with or without food. Key factors to consider when prescribing ledipasvir-sofosbuvir are drug interactions including those mediated by the P-glycoprotein transporter and increased pH, cost of the drug or insurance coverage, comorbid conditions, and patient and provider preferences. Postmarketing experience and ongoing clinical trials will further define the safety and role of ledipasvir-sofosbuvir in the treatment of HCV genotype 1.

Physician–pharmacist collaboration for oral chemotherapy monitoring: Insights from an academic genitourinary oncology practice

Background

Oral chemotherapy is being routinely used in metastatic castrate-resistant prostate and renal cell cancer. Although convenient, these drugs require monitoring for adherence, toxicity, and drug interactions to maximize outcomes. Oncology pharmacists have the training and expertise that place them in an optimal position to collaboratively provide medication therapy management.

Methods

A board-certified oncology pharmacist, working in collaboration with a medical oncologist, initiated an oral chemotherapy–monitoring program. The pharmacist provided education, completed medication therapy management; monitored for adherence and toxicity; and recommended treatment of toxicity and supportive care issues. Patient encounters included one of the following: collaboration with medical oncologist visit, pharmacist visit, or telephone or email follow-up between visits.

Results

From December 2012 to May 2014, the pharmacist had 123 encounters with 20 patients with either metastatic prostate ( n = 17) or renal cell cancer ( n = 3). All patients were males (median age 80 years). Most encounters were clinic visits, in collaboration with physician visit or alone (52%); 36% were telephone encounters, and 11.3% were email follow-ups. Medication-related problems were identified in 25% of the 315 assessments made. Problems included: adverse drug reactions, 40%; inappropriate therapy, 20%; and noncompliance, 18%. Recommendations included: modification of laboratory monitoring, 25%; cancer or non-cancer therapy modification, 12%; drug discontinuation, 6.9%. Non-cancer therapy-related drug information and coordination of care accounted for 30% of recommendations.

Conclusion

Our program led to identification of a number of potentially clinically significant issues for patients on oral chemotherapy and demonstrated the benefit of the pharmacist in the multidisciplinary team to assist in addressing them.

Atypical presentation of fever as hypersensitivity reaction to oxaliplatin

Oxaliplatin, a third-generation, platinum-based agent is widely used, most commonly in the FOLFOX (5-fluorouracil, leucovorin and oxaliplatin) regimen, which is the first-line therapy in metastatic colorectal adenocarcinoma and adjuvant chemotherapy in stage III colorectal cancer. Platinum-based products are well known for causing hypersensitivity reactions. Fever associated with oxaliplatin-hypersensitivity reactions typically follows a specific pattern. It usually starts during the oxaliplatin infusion or immediately after (within hours instead of days) and happens after several administrations (mean 2–25) with unpredictable clinical presentations. We report a case of oxaliplatin-induced hypersensitivity reaction manifesting as fever but with unusual presentation than the aforementioned features.

Late onset imatinib-induced Stevens-Johnson syndrome

Imatinib, a BCR-ABL tyrosine kinase inhibitor, is known to cause mild to moderate cutaneous reactions in up to approximately 20% of patients. It rarely causes severe reactions, such as Stevens-Johnson syndrome, which can be life threatening. Typically, these rashes occur within two months of initiating therapy. We report a case of Stevens-Johnson syndrome induced by imatinib after several years of therapy, but later successfully was treated with nilotinib therapy.

Potential new gene therapy option with sitimagene ceradenovec for newly diagnosed patients with glioblastoma multiforme

Glioblastoma multiforme (GBM) is associated with a poor prognosis with a 5-year survival rate of less than 5%, making GBM one of the most aggressive neoplastic malignancies. However significant strides have been made over the past few years with respect to understanding the pathophysiology as well as treatment modalities. The use of local therapies, particularly gene therapy, has been evaluated, but have yet to make a major clinical impact on treatment of GBM. In a study published by Westphal and colleagues in The Lancet Oncology, the use of sitimagene ceradenovec, a first generation replication-deficient adenovirus containing a prodrug converting enzyme, herpes-simplex virus thymidine kinase, followed by intravenous ganciclovir administration and standard therapy was evaluated compared with standard therapy alone. Patients who received sitimagene ceradenovec had improved time to death or re-intervention, but did not show improvement in overall survival. Patients receiving sitimagene ceradenovec experienced more adverse effects related to treatment, including seizures and hyponatremia. While further studies need to be conducted to determine clinical significance, gene therapy appears to be a viable approach for patients who may be resistant to chemotherapy.

Granisetron vs ondansetron for prevention of nausea and vomiting in hematopoietic stem cell transplant patients: results of a prospective, double-blind, randomized trial

The serotonin type-3 (5-HT3) antagonists represent a significant advance in the prevention of acute nausea and vomiting (N/V) from highly emetogenic chemotherapy. We sought to determine if any differences in efficacy or adverse effects exist between two such agents, ondansetron and granisetron, during conditioning therapy for hematopoietic stem cell transplantation (HSCT). Patients were randomized to receive either ondansetron 0.15 mg/kg intravenously every 8 h or granisetron 10 microg/kg intravenously daily. Additionally, all patients received scheduled dexamethasone and lorazepam. Prophylaxis was continued until 24 h after completion of chemotherapy. Nausea and distress were measured subjectively with visual analog scales and emetic episodes were quantified. Of the 110 randomized patients, 96 were evaluable for efficacy and safety. No significant differences in efficacy were observed between the ondansetron- and granisetron-treated patients, evaluated by comparing the degree of nausea and distress, number of emetic episodes and overall control of emesis. The adverse effects were also comparable and no patients were removed from study because of severe toxicities. This trial demonstrates that ondansetron and granisetron are equally effective at preventing acute N/V associated with conditioning therapy frequently used for HSCT. The agent of choice should be based on drug acquisition cost or preference.

Pegaspargase: an alternative?

OBJECTIVE

To review the chemistry, pharmacology, pharmacokinetics, clinical activity, adverse effects, dosage, and administration guidelines for pegaspargase.

DATA SOURCES

A MEDLINE search (1980-1996), a CANCERLIT search (1983-1996), and a CURRENT CONTENTS search (1980-1996) using the terms pegaspargase, PEG-asparaginase, PEG-L-asparaginase, polyethylene glycol L-asparaginase, polyethylene glycol conjugated L-asparaginase, and Oncaspar were conducted.

STUDY SELECTION AND DATA EXTRACTION

All articles were considered for possible inclusion in this review. Abstracts were included only when they were judged to add critical information not otherwise available in the medical literature.

DATA SYNTHESIS

L-Asparaginase has been a main component of treatment regimens for acute lymphocytic leukemia. A key limiting factor of L-asparaginase use has been the development of hypersensitivity to the drug. Recently, a polyethylene glycol (PEG) conjugated form of L-asparaginase, pegaspargase, has been made available. PEG modification of L-asparaginase has been shown to alter the tendency of the enzyme to induce an immune response and to extend the half-life of the drug. The majority of patients with hypersensitivity to the native enzyme preparations tolerate pegaspargase without further clinical hypersensitivity. The adverse effect profile of pegaspargase is similar to that of the native forms of L-asparaginase. The recommended dosage of pegaspargase is 2500 IU/m2 administered by intramuscular or intravenous injection every 2 weeks in combination with other chemotherapeutic agents.

CONCLUSIONS

Pegaspargase is a safe, effective alternative to L-asparaginase in patients who have had clinical hypersensitivity reactions to both Escherichia coli- and Erwinia carotovora-derived L-asparaginase. However, pegaspargase should not be routinely substituted for L-asparaginase.

Valproate in status epilepticus

In patients with intractable status epilepticus who have not responded to therapy with benzodiazepines, phenytoin, and barbiturates, valproate may be a reasonable option. Extemporaneously prepared valproate rectal suppositories or retention enemas have been given in dosages of 200-1200 mg q6h in addition to phenytoin, phenobarbital, or both in adults. The pediatric dose used was 15-20 mg/kg, in addition to phenytoin and/or phenobarbital.