Ondansetron: a new antiemetic for patients receiving cisplatin chemotherapy

Evaluation of Cisplatin Combined with Ondansetron in Ehrlich Ascites Carcinoma in Vitro and in Vivo

Aims and background

Nausea and vomiting occur in the majority of patients receiving cisplatin (CDDP) chemotherapy. Ondansetron, a new 5-HT3 receptor antagonist, has been used effectively to control CDDP-induced nausea and vomiting. This study examined the potential of ondansetron to interfere with CDDP antitumor activity and toxicity in Ehrlich ascites carcinoma (EAC).

Methods

The influence of ondansetron on CDDP cytotoxicity was evaluated using EAC cells in culture. In addition, the influence of ondansetron pretreatment on CDDP-induced antitumor activity and host tissue toxicity was studied in EAC-bearing mice.

Results

Ondansetron (0.25 μM) enhanced CDDP (0–32 μM) cytotoxicity against EAC cells in vitro. In EAC-bearing mice ondansetron (0.2 mg/kg, ip) administered 1 h before CDDP (7 mg/kg, ip) did not modify the antitumor activity of CDDP. CDDP (7 mg/kg, ip) single treatment induced significant increases in blood urea nitrogen (2-fold) and serum creatinine (2.5-fold) and significant decreases in hematocrit (25%) and white blood cell count (39%) compared to saline treatment. Mice receiving ondansetron 1 h before CDDP showed no significant enhancement of CDDP-induced nephrotoxicity or myelosuppression compared to those pretreated with saline receiving the same dose of CDDP.

Conclusions

This study suggests that the use of ondansetron to control CDDP-induced nausea and vomiting does not affect CDDP antitumor efficacy.

Phase II study of fosaprepitant + 5HT3 receptor antagonist + dexamethasone in patients with germ cell tumors undergoing 5-day cisplatin-based chemotherapy: a Hoosier Cancer Research Network study

PURPOSE

A phase III study adding aprepitant to a 5HT3 receptor antagonist (5HT3-RA) plus dexamethasone in germ cell tumor (GCT) patients treated with 5-day cisplatin combination chemotherapy demonstrated a significant improvement in complete response (CR) (J Clin Onc 30:3998-4003, 2012). Fosaprepitant has demonstrated non-inferiority compared to aprepitant in single-day cisplatin chemotherapy and is approved as a single-dose alternative. This single-arm phase II study is the first clinical trial evaluating fosaprepitant in patients receiving multi-day cisplatin regimen.

METHODS

GCT patients receiving a 5-day cisplatin combination chemotherapy were enrolled. Fosaprepitant 150 mg was given IV on days 3 and 5. A 5HT3-RA days 1-5 (days 1, 3, and 5, if palonosetron) plus dexamethasone 20 mg days 1 and 2 and 4 mg po bid days 6, 7, and 8 was administered. Rescue antiemetics were allowed. The primary objective was to determine the CR rate-no emetic episodes or use of rescue medications. Accrual of 64 patients was planned with expected CR > 27 %.

RESULTS

Sixty-five patients were enrolled of whom 54 were eligible for analysis. Median age was 33. Fifty-one patients received bleomycin, etoposide, and cisplatin (BEP) chemotherapy. CR was observed in 13 (24.1 %) patients (95 % Agresti-Coull binomial C.I. 14.5 %, 37.1 %).

CONCLUSION

The data in this phase II study, in contrast to our prior phase III study, appears to indicate a lower CR rate with the substitution of fosaprepitant for aprepitant. It is unknown whether the substitution of fosaprepitant for aprepitant provides the same benefit in multi-day cisplatin that was achieved with single-day cisplatin. Trial registration Clinical trial information NCT01736917.

Management of Chemotherapy Induced Nausea and Vomiting in Patients on Multiday Cisplatin Based Combination Chemotherapy

Introduction of cisplatin based chemotherapy has revolutionized the treatment of germ cell tumors. A common side effect of multiday cisplatin chemotherapy is severe nausea and vomiting. Considerable progress has been made in the control of these side effects since the introduction of cisplatin based chemotherapy in the 1970s. Germ cell tumor which is a model for a curable neoplasm has also turned into an excellent testing ground to develop effective strategies to prevent chemotherapy induced nausea and vomiting (CINV) in multiday cisplatin based regimens. The use of combination of a 5-hydroxytryptamine (HT)3 receptor antagonist, a neurokinin-1 (NK1) antagonist, and dexamethasone has greatly improved our ability to prevent and control acute and delayed CINV. Mechanism and pattern of CINV with multiday chemotherapy may differ from those in single day chemotherapy and therefore efficacy of antiemetic drugs as observed in single day chemotherapy may not be applicable. There are only few randomized clinical trials with special emphasis on multiday chemotherapy. Further studies are essential to determine the efficacy, optimal dose, and duration of the newer agents and combinations in multiday cisplatin based chemotherapy.

Randomized, Double-Blind, Placebo-Controlled, Phase III Cross-Over Study Evaluating the Oral Neurokinin-1 Antagonist Aprepitant in Combination With a 5HT3 Receptor Antagonist and Dexamethasone in Patients With Germ Cell Tumors Receiving 5-Day Cisplatin Combination Chemotherapy Regimens: A Hoosier Oncology Group Study

Purpose

Aprepitant, a 5-HT3 receptor antagonist (5HT3-RA), and dexamethasone are standard antiemetic therapy for prevention of single-day, cisplatin-induced nausea and vomiting. We conducted a double-blind, placebo-controlled phase III cross-over study that compared aprepitant to placebo combined with standard antiemetic prophylaxis (a 5HT3-RA and dexamethasone) in patients receiving 5 days of cisplatin combination chemotherapy for testicular cancer.

Patients and Methods

Patients receiving two consecutive identical courses of a 5-day cisplatin-based chemotherapy were randomly assigned to aprepitant 125 mg on day 3 and 80 mg per day on days 4 through 7 or to placebo with the initial course and crossover to the opposite treatment with the second course. The primary objective was complete response (CR). Secondary end points were emetic episodes (acute and delayed), nausea measurement based on a visual analog scale (VAS), and patient-stated preference after the second study cycle.

Results

In all, 71 patients were screened for the study and 69 were evaluable. Thirty-five patients were randomly assigned to receive aprepitant and 34 to receive placebo for the first course. Forty-two percent achieved CR with aprepitant compared with 13% with placebo (P < .001). Eleven patients (16.2%) had at least one emetic episode during the aprepitant cycle versus 32 patients (47.1%) with placebo. Thirty-eight patients preferred the aprepitant cycle whereas 11 preferred placebo (P < .001). There was no statistical difference in VAS for nausea, but it was numerically superior with aprepitant. There was no toxicity with aprepitant compared with placebo.

Conclusion

There was a significant improvement in CR rate with aprepitant combined with a 5HT3-RA and dexamethasone. Patient preference strongly favored the aprepitant cycle.

Cardiovascular risk factors and morbidity in long-term survivors of testicular cancer: a 20-year follow-up study

PURPOSE

To evaluate the prevalence of cardiovascular risk factors and long-term incidence of cardiovascular disease (CVD) in survivors of testicular cancer (TC).

METHODS

Overall, 990 men treated for unilateral TC (1980 to 1994) were included in this national follow-up study (2007 to 2008). They were categorized into four treatment groups: surgery (n = 206), radiotherapy only (RT; n = 386), chemotherapy only (n = 364), and combined RT/chemotherapy (n = 34). Age-matched male controls from the general population (ie, NORMs) were included (n = 990). Survivors of TC who were diagnosed with CVD before or within 2 years after the TC diagnosis were excluded from analyses of CVD end points.

RESULTS

Median observation time was 19 years (range, 13 to 28 years). All cytotoxic treatment groups had significantly increased prevalences of antihypertensive medication, and survivors in the RT and RT/chemotherapy groups had higher prevalences of diabetes (RT: odds ratio [OR], 2.3; 95% CI, 1.5 to 3.7; RT/chemotherapy: OR, 3.9; 95% CI, 1.4 to 10.9) compared with NORMs. Overall 74 survivors of TC (8.0%) experienced atherosclerotic disease during follow-up. Increased risks for atherosclerotic disease were observed in age-adjusted Cox regression analyses after any cytotoxic treatment when compared with surgery only (RT: hazard ratio [HR], 2.3; 95% CI, 1.04 to 5.3; chemotherapy: HR, 2.6; 95% CI, 1.1 to 5.9; RT/chemotherapy: HR, 4.8; 95% CI, 1.6 to 14.4). Treatment with cisplatin, bleomycin, and etoposide (BEP) alone had a 5.7-fold higher risk (95% CI, 1.9 to 17.1 fold) for coronary artery disease compared with surgery only and a 3.1-fold higher risk (95% CI, 1.2 to 7.7 fold) for myocardial infarction compared with NORMs.

CONCLUSION

Treatment with infradiaphragmatic RT and/or cisplatin-based chemotherapy, particularly the BEP regimen, increases the long-term risk for CVD in survivors of TC.

Antiemetic therapy for multiple-day chemotherapy and additional topics consisting of rescue antiemetics and high-dose chemotherapy with stem cell transplant: review and consensus statement

This paper will evaluate various topics related to chemotherapy-induced nausea and vomiting. The results published reflect a consensus conference convened in Perugia, Italy. The topics discussed include antiemetic therapy of multiple-day chemotherapy, high-dose chemotherapy, and rescue antiemetics.

Palonosetron plus dexamethasone for prevention of chemotherapy-induced nausea and vomiting in patients receiving multiple-day cisplatin chemotherapy for germ cell cancer

GOALS OF WORK

The aims of this study were to assess the safety and antiemetic efficacy of multiple-day dosing of palonosetron plus dexamethasone in patients receiving highly emetogenic multiple-day cisplatin-based chemotherapy for germ cell tumors.

MATERIALS AND METHODS

Forty-one men undergoing 5-day cisplatin-based chemotherapy for testicular cancer received palonosetron 0.25 mg IV once daily 30 min before chemotherapy on days 1, 3, and 5 plus IV dexamethasone 20 mg before chemotherapy on days 1 and 2, and 8 mg PO bid on days 6 and 7 and 4 mg bid on day 8. Safety and efficacy were assessed in 24-h intervals for 9 days. Efficacy endpoints included emesis, intensity of nausea and its interference with patient functioning, and rescue antiemetic use. A subset of patients (n = 11) was studied for electrocardiograph effects and pharmacokinetic evaluation.

MAIN RESULTS

This multiple-day antiemetic regimen was safe, with headache and constipation the most common treatment-related adverse events, mostly mild. Neither adverse events nor electrocardiographic changes appeared to increase in frequency, duration, or intensity over time despite a 1.42-fold systemic accumulation of palonosetron with repeated doses. The majority of patients had no emesis at any time throughout days 1-5 (51%) or days 6-9 (83%), had no moderate-to-severe nausea, and did not require rescue medication. Most patients reported that nausea had no significant effect on daily functioning on days 1-4 (72%) and days 5-9 (85%).

CONCLUSIONS

Palonosetron on days 1, 3, and 5, along with a regimen of dexamethasone, was safe and well tolerated and effectively controlled both nausea and emesis in patients undergoing 5-day cisplatin-based chemotherapy for testicular cancer.

Emetic potential of daily oral etoposide

BACKGROUND

Chemotherapeutic agents are classified by their degree of emetogenicity. Highly and moderately emetogenic agents require antiemetic prophylaxis for chemotherapy-induced nausea and vomiting. Intravenous etoposide is listed as having low emetic potential. However, oral etoposide is categorized as having moderate emetogenicity. Daily oral etoposide is used in refractory germ cell cancer patients. We prospectively evaluated the emetic potential of oral etoposide in this patient population.

MATERIALS AND METHODS

Between August 2003 and February 2006, 16 patients with refractory germ cell cancer received single-agent, daily oral etoposide 50 mg/M(2) for 21 consecutive days every 4 weeks. All patients had progressed after cisplatin combination chemotherapy and had received high-dose chemotherapy with carboplatin plus etoposide (intravenously) with peripheral blood stem cell transplant. No patient received prophylactic antiemetics. Patients completed a six-question Multinational Association of Supportive Care in Cancer (MASCC) antiemetic tool during each day of etoposide during the first 21-day course. Nausea intensity and duration were recorded. Number of emetic episodes and any antiemetic medications were recorded.

RESULTS

All 16 patients completed the six-question MASCC form. Eleven of 16 had no nausea or vomiting and two other patients had only minimal nausea, despite absence of any prophylactic antiemetics. Only two patients required antiemetic support. Two patients experienced emesis for a single episode. One patient had nausea on days 9-20 with a MASCC rating of 3-6, and one patient had continued mild nausea (MASCC rating 1-3) for all 21 days.

CONCLUSIONS

Daily oral etoposide has a low probability of producing chemotherapy-induced nausea and/or vomiting and, in our opinion, does not require prophylactic antiemetics.

Gastrointestinal toxicity of chemotherapeutic agents

Chemotherapy-induced toxicities commonly occur in sites within the gastrointestinal (GI) tract and account for dose-limiting effects. These toxicities are major contributing factors to dose reduction, delays, and cessation of cancer treatment. Through intensive therapies including surgery, combination chemotherapy, hormonal therapy, and targeted therapy, an increasing number of patients with cancer are experiencing improved survival and long-term disease-free survival, as well as palliation of disease-related symptoms. Thus, GI toxicities should be predicted and appropriate interventions initiated to prevent them when possible and provide effective supportive measures and comprehensive follow-up care. This review will discuss the etiology, incidence, prevention, and treatment of GI toxicities of cancer chemotherapy.

Headache related to brain tumors

Headache is one of the most common somatic complaints of patients seeking medical care. Most headaches are not of serious cause and can be diagnosed easily with a good history and physical examination. The challenges to the physician are to determine when underlying intracranial pathology may be causing the symptoms and signs, and to identify the few patients in whom a tumor is the cause of the headache. The subject of headache in patients with brain tumors has been reviewed in neurologic textbooks and in several investigations before, as well as after, modern imaging diagnostic techniques became available. Headache can also manifest as an acute or chronic complication of radiation treatment and/or chemotherapy in patients with intracranial neoplasm, but there are few data in the literature specifically addressing this subject. This article provides an overview of headache in patients with primary and secondary brain tumor, including headache characteristics, the putative mechanism for these headaches, the role of diagnostic testing, and the general principles of management.

The antiemetic effect of a novel tropisetron patch in anticancer agents-induced kaolin pica model using rats

The efficacy of a novel transdermal patch containing tropisetron, a 5-hydroxytryptamine 3 (5-HT(3)) receptor antagonist, against emesis induced by anticancer agents were evaluated, in comparison with the effect of traditional tropisetron injection, in rats. The antiemetic effects were assessed via the inhibitory activity on the anticancer agent-induced kaolin-consuming behavior, a pica model representing vomiting in emesis-resistant rodents. The tropisetron patch (10mg/patch, 3.5cm(2)) was attached on the shaved back area of rats. Eight h later, each anticancer agent, cisplatin (10mg/kg, i.v.), cyclophosphamide (200mg/kg, i.p.) or doxorubicin (8mg/kg, i.v.), was administered, and thereafter, daily kaolin consumption was measured for 3 days. In comparison, the effect of daily injection of tropisetron (2mg/kg, i.v.), given 10min, 24 and 48h after the anticancer agent administration, was also evaluated. Kaolin intake greatly increased to 21, 17 and 10 folds of control ingestion on the first day after administration with the anticancer agents, cisplatin, cyclophosphamide and doxorubicin, respectively, and then gradually decreased to near control level on day 3. Such anticancer agent-induced increases in the kaolin consumption were remarkably attenuated by the attachment of tropisetron patch, resulting in the reduction to half levels, which is comparable to the efficacy of daily tropisetron injection. In particular, the blood concentration of tropisetron following patch attachment reached a maximum level of 30-40ng/ml in 12h and exhibited a plateau until detachment of the patch, in contrast to a rapid elimination with a half-life of 2.21h after injection of the drug. Taken together, it is suggested that the novel tropisetron patch could be a promising regimen for the relief of emesis, based on the long-term antiemetic effects on the diverse anticancer agents and the convenience to use the transdermal delivery system for the cancer patients who have difficulty in taking drugs due to surgical operation or gastrointestinal dysfunction.

Antiemetic therapy for multiple-day chemotherapy and high-dose chemotherapy with stem cell transplant: review and consensus statement

The objective of this paper is to evaluate the efficacy of modern antiemetic therapy for chemotherapy-induced nausea and vomiting for patients receiving multiple-day or high-dose chemotherapy. Published phase II and phase III studies as well as their personal experiences were evaluated by the authors to develop this consensus statement. The largest published experience with multiple-day chemotherapy is with 5-day cisplatin combination chemotherapy. The introduction of 5-HT3 antagonists greatly improved emetic control. However, day 4-5 nausea as well as delayed nausea and vomiting remains a clinical problem despite the inclusion of dexamethasone. A 5-HT3 antagonist plus dexamethasone is the preferred current option for patients receiving high-dose chemotherapy with stem cell transplant. However, the results do not appear as successful as for highly emetic standard-dose chemotherapy.

Headaches and brain tumors

A careful history and physical examination remain the most important aspects of headache assessment. enabling the neurologist to decide if any further studies are necessary. Only a minority of patients who have headaches have brain tumors; however, recognition of the headaches characteristically associated with tumors is most important. Some locations are more likely to produce headache (eg, a posterior fossa tumor causes headache more often than a supratentorial tumor). Rapidly growing tumors are more likely to be associated with headache. Uncommon headache presentations can occur with tumors, includin paroxysmal cough, cluster headache, and TACs. The classic brain tumor headache is not as common as a tension-type presentation or migraine. Patients who have prior primary headaches may have more headache symptoms if they have a tumor and of course they still have their primary headache disorder. Mass lesions progress and inevitably develop other symptoms and signs besides headache, and these new symptoms and signs must be sought and found. Metastatic leptomeningeal involvement can present with headache and spinal pain in the neck and back. Imaging of headache patients for tumors, if they have primary headache disorders, such as migraine and typical cluster, generally is not cost effective but is necessary if there are any atypical features. Treatment of headache in patients who have metastatic brain tumors should be aggressive in terms of pain and symptoms control. Treatment of primary CNS tumors is dictated by the kind of neoplasm and site, but control of headache should not be ignored.

The effect of electroacupuncture as an adjunct on cyclophosphamide-induced emesis in ferrets

The effect of electroacupuncture (EA) on cyclophosphamide-induced emesis in ferrets was studied at acupuncture point Neiguan (P6) with various electrical stimulation parameters (5-100 Hz, 1.5-3 V, 5-20 min, n=6/group). The combination therapy of EA (100 Hz, 1.5 V and 10 min) with the lower doses of ondansetron (0.04 mg/kg), droperidol (0.25 mg/kg) and metoclopramide (2.24 mg/kg) significantly reduced the total number of emetic episodes by 52%, 36% and 73%, respectively, as well as the number of emetic episodes in the first phase as compared to the sham acupuncture control (P<.01). These EA/drug combinations also showed a significant effect in preventing emesis as compared to either EA or drug alone (P<.05). The present study suggests that acupuncture may be useful as an adjunctive therapy in the treatment of chemotherapy-induced emesis.

Improvement of cisplatin-induced emesis and delayed gastric emptying by KB-R6933, a novel 5-HT3 receptor antagonist

The effects of a novel 5-hydroxytryptamine3 (5-HT3) receptor antagonist, KB-R6933, 6-amino-5-chloro-1-isopropyl-2-(4-methyl-1-piperazinyl)-benzimidazole dimaleate, on emesis and delayed gastric emptying induced by cisplatin were assessed in experimental models. Prophylactic intravenous or oral treatment with KB-R6933 prolonged the latent period until the first emetic episode and decreased the number of emetic episodes induced by cisplatin in ferrets. KB-R6933 immediately inhibited the subsequent emesis when administered to the ferrets which exhibited established vomiting after administration of cisplatin. In rats treated with cisplatin, the gastric emptying rate was significantly reduced. KB-R6933 reversed the reduction of gastric emptying induced by cisplatin. These results suggest that KB-R6933 is an antiemetic agent, and could improve the cisplatin-induced delay of gastric emptying.

Navoban (tropisetron, ICS 205-930) and dexamethasone combination in the prevention of vomiting for patients receiving preconditioning high-dose chemotherapy before marrow transplantation

The anti-emetic efficacy of a combination of tropisetron and dexamethasone was studied in 33 patients who underwent bone marrow transplantation. Another 50 patients receiving conventional anti-emetic therapies in bone marrow transplantation served as control. On the first and second days of preconditioning chemotherapy, 51% and 36% respectively of patients in the tropisetron and dexamethasone group did not experience vomiting, compared with only 12% and 10% of control group patients (P < 0.001). The mean number of episodes of vomiting in the tropisetron and dexamethasone group was also significantly lower than in the control group (0.97+/-1.65 vs 3.50+/-2.45 and 1.30+/-1.40 vs 4.44+/-2.91 respectively, both P < 0.001). Control of vomiting in the two groups was not significantly different during days 3-6. Analysis of patients receiving busulfan and cyclophosphamide as the preconditioning regimen still showed better anti-emetic control in the tropisetron and dexamethasone group than in the control group on the first two days of treatment (total control rate 33.3% vs 6.5% and 44.4% vs 12.9% respectively, P < 0.001). Patients given tropisetron and dexamethasone combination more frequently suffered from dizziness and burning sensation of the chest. However, diarrhea and extrapyramidal symptoms were the most frequent adverse effects seen after using conventional anti-emetic combination. The combination of tropisetron and dexamethasone was thus superior to conventional anti-emetic combinations in preventing vomiting during preconditioning period of bone marrow transplantation. The adverse effects of this combination were minimal and well tolerated by patients.

A comparative study of intravenous granisetron versus intravenous and oral ondansetron in the prevention of nausea and vomiting associated with moderately emetogenic chemotherapy

We conducted a prospective, randomized, open, single-center, parallel group study comparing the anti-emetic efficacy and toxicity of granisetron with that of ondansetron in patients receiving moderately emetogenic chemotherapy. From December 1994 to May 1995, patients who were to receive moderately emetogenic chemotherapy for the first time or who had not received chemotherapy (80 to 100 mg/m2 of cisplatin or 40 mg/m2 of doxorubicin) within 4 weeks previously were enrolled in this study. The following anti-emetic regimens were used: 3 mg of granisetron were given intravenously before chemotherapy for a single dose; 8 mg of ondansetron were given intravenously before chemotherapy and then every 8 hours for a total of 3 doses, plus 8 mg of an oral maintenance dose every 12 hours for 5 consecutive days. We evaluated 97 patients (48 received granisetron and 49 received ondansetron). In the first 24 hours after chemotherapy, complete and major responses were achieved in 76.6% of the patients receiving granisetron and in 72.9% of patients receiving ondansetron (p = 0.9033). Additionally, there was no difference in the control of delayed nausea and vomiting between the two groups (51.1% versus 54.2%, p = 0.9200), and there were no significant adverse effects or toxicities. We have concluded that a single dose of granisetron is as effective in prophylaxis of emesis induced by moderately emetogenic chemotherapy as a triple dose of ondansetron plus oral maintenance.

Biphasic emetic response of cyclophosphamide in the ferret

Cyclophosphamide (177 mg/kg, IV: n = 8) produced a biphasic emetic response in the ferret with a mean +/- SE of 23.3 +/- 4.0 emetic episodes during a 4-h observation period. The emetic profile of cyclophosphamide showed a first phase with 18.6 +/- 3.9 episodes and a second phase with 4.7 +/- 1.2 episodes. Ondansetron (0.07 and 0.13 mg/kg, IV) and droperidol (0.25 and 0.79 mg/kg, IV) significantly reduced the number of emetic episodes in the first phase. Metoclopramide (2.24, 4.08, and 7.07 mg/kg, IV) also significantly reduced the number of emetic episodes in the first phase, and the dose of 7.07 mg/kg completely prevented emetic episodes in the second phase. In addition, ondansetron-treated ferrets (0.04, 0.07, and 0.13 mg/kg, IV) had a significant increase in the number of emetic episodes in the second phase.

Progress in reducing nausea and emesis. Comparisons of ondansetron (Zofran), granisetron (Kytril), and tropisetron (Navoban)

BACKGROUND

Nausea and vomiting are the most distressing side effects associated with the administration of chemotherapy for neoplastic diseases. Nausea, in particular, often had been ignored in studies of chemotherapy side effects. Recently, progress has been made in the control of chemotherapy-induced nausea and vomiting, due, in part, to a better understanding of the physiologic mechanisms involved.

METHODS

This paper reviews recent advances in the control of emesis, focusing on pharmacologic treatments.

RESULTS

The efficacy and safety of the serotonin (5-HT3) receptor antagonists granisetron, ondansetron, and tropisetron in the control of acute and delayed emesis and emesis induced by repeat-cycle chemotherapy are summarized. Although differences in study design and definitions of response criteria have made it difficult to compare the studies that have evaluated these three agents, the overall body of literature supports several clinical findings.

CONCLUSIONS

(1) The 5HT3 antiemetic agents have been shown to be clinically more effective in the control of nausea and emesis than previously used agents. (2) No one of the three has demonstrated consistently greater efficacy. (3) Efficacy appears to be more pronounced for cisplatin-containing regimens than for moderate or less emetogenic chemotherapy regimens. (4) Effectiveness of the 5HT3 agents appears to be less for delayed nausea and emesis than for acute symptoms. Potential control of anticipatory nausea and emesis has not been investigated. (5) Control over nausea appears to be significantly less than control over emesis. In the studies in which it has been measured, nausea control remains incomplete for approximately half the patients given 5HT3 agents. (6) The efficacy of the agents appears to diminish across repeated days and, perhaps, across repeated chemotherapy cycles. (7) The addition of a steroid such as dexamethasone increases the efficacy of both 5HT3 and other antiemetic agents. This effect also seems to apply to delayed nausea and emesis.

Antiemetics in cancer chemotherapy: historical perspective and current state of the art

Chemotherapy-related nausea and vomiting can today be controlled with available antiemetics in a high percentage of patients but emesis remains a problem for some patients, with certain drugs and with repeated cycles of chemotherapy. The fundamental steps of clinical research in antiemetics towards the improvement of the control of nausea and vomiting with new drugs or combinations are presented. Special emphasis is given to cisplatin-induced nausea and vomiting because of the frequency and relevance of this phenomenon. The use of high-dose metoclopramide, its combination with steroids, and later the addition of lorazepam or diphenhydramine represented the evolving standard of the 1980s, with the level of complete protection from vomiting improving from 30%-40% to 60%-70% with the three-drug combination. The introduction of new agents such as the 5-hydroxytryptamine 3 (5-HT3) receptor antagonists has recently offered new possibilities because of their activity and lack of toxicity. In particular, the combination of ondansetron plus dexamethasone is today the most efficacious and least toxic antiemetic treatment for prevention of emesis in patients treated with a single high dose or low repeated doses of cisplatin. A comparison of different 5-HT3 antagonists, always in combination with steroids, is now considered necessary. For patients treated with moderately emetogenic chemotherapy the use of steroids can still be considered the standard treatment. In this setting, the role of 5-HT3 receptor antagonists, alone or in combination with steroids, has to be better defined through large, well-planned clinical trials, which should have a cost-effectiveness analysis as one of their goals.

Comparison of ondansentron versus ondansentron plus methylprednisolone as antiemetic prophylaxis during cisplatin-containing chemotherapy

We compared the antiemetic efficacy of ondansentron versus ondansentron and corticosteroids in cisplatin-induced emesis. None of our patients had received prior chemotherapy. All patients received chemotherapy including cisplatin 100 mg/m2. Forty patients received ondansentron alone (Group A) and 40 the combination of ondansentron and methylprednisolone (Group B). Ondansentron was given at a dose of 8 mg in 100 mL N/S over 10 min by intravenous infusion. The initial dose was administered before the cisplatin and was followed by 8 mg orally in the afternoon and before sleeping the first day of chemotherapy. During the next 2 days, the patients received 8 mg orally 3 times daily. Methylprednisolone was given as an intravenous bolus of 40 mg before chemotherapy and then together with each dose of ondansentron at a dose of 16 mg orally. Group A had significantly longer duration of nausea after chemotherapy than group B (117 +/- 111 min, 62 +/- 71 min, P < 0.013). The response on emesis was also improved in group B, especially the day of chemotherapy [treatment failure: group A: 13 patients (30%) versus group B: 5 patients (11.6%), P < 0.03] and the next day [complete response: group A: 17 patients (39.5%) versus group B: 30 patients (69.7%), P < 0.005]. Patients in group B presented more sedative effects (P < 0.001) and better appetite (P < 0.02) than patients in group A. There were no other significant differences in side effects (activity, headache, constipation, etc). We conclude that corticosteroids improve the antiemetic efficacy of ondansentron in cisplatin-induced chemotherapy, and should be included in antiemetic regimens.

A sensitive radioimmunoassay, combined with solid-phase extraction, for the sub-nanogram per ml determination of ondansetron in human plasma

The development of a radioimmunoassay, incorporating solid-phase sample extraction, suitable for the subnanogram per ml determination of ondansetron base in human plasma is described. The antiserum was raised in Soay sheep following primary and booster immunizations with an immunogen prepared by conjugating 9-(carboxypropyl)-ondansetron to bovine thyroglobulin. The radioligand consisted of ondansetron specifically tritium-labelled on the N-methyl group of the indole moiety. The solid-phase extraction method, using a cyanopropyl sorbent, was introduced to remove cross-reacting metabolites and to enhance assay sensitivity. The calibration range is 0.05-2.40 ng ml-1 using a 1 ml sample of human plasma; inter- and intra-assay bias and precision are < +/- 13% and < 10% over this concentration range, respectively. The assay drift, measured as the difference in concentration values for quality control samples assayed immediately before and after the sequence of test plasma samples, is < +/- 10% for run sizes of up to 54 samples.

The effect of ondansetron on atracurium-induced neuromuscular blockade

STUDY OBJECTIVE

To determine whether treatment with ondansetron, a new antiemetic drug, affects nondepolarizing neuromuscular blockade.

DESIGN

Randomized, double-blind, prospective study.

SETTING

Operating room at a university medical center.

PATIENTS

30 ASA physical status I and II patients scheduled for elective surgery.

INTERVENTIONS

After the induction of anesthesia with midazolam 2 to 4 mg/kg, sodium thiopental 6 to 8 mg/kg, and fentanyl 4 to 8 micrograms/kg, the ulnar nerve was stimulated at the wrist through subcutaneous needle electrodes at a frequency of 0.15 Hz. The response to stimulation was measured and recorded with a force-displacement transducer applied to the thumb. Patients were randomized to one of three treatment groups. A steady baseline to ulnar nerve stimulation with nitrous oxide-oxygen-opioid-thiopental anesthesia was established. The first study group (Group 1) received a placebo, the second group (Group 2) received 8 mg of ondansetron, and the third group (Group 3) received 16 mg of ondansetron as an intravenous infusion over 5 minutes. Patients were then given incremental doses of atracurium 0.05 mg/kg at 3-minute intervals to establish approximately 95% twitch inhibition so as to construct a dose-response curve. An atracurium infusion was then begun to maintain a constant degree of neuromuscular blockade. At the end of surgery, patients were allowed to recover spontaneously, or pharmacologic antagonism of residual neuromuscular blockade was achieved with neostigmine 0.05 mg/kg and glycopyrrolate 0.01 mg/kg. Mechanomyographic response to train-of-four stimuli (2 Hz for 2 seconds) every 20 seconds was monitored during the atracurium infusion and recovery from neuromuscular blockade.

MEASUREMENTS AND MAIN RESULTS

Log dose-response curves were determined for the study groups and compared using analysis of variance (ANOVA). The 50%, 75%, and 95% effective doses (ED50, ED75, and ED95) were calculated from the equation describing the log dose-response. Maintenance infusion rates were determined, and the neostigmine-accelerated recovery index of 25% to 75% was measured for each group. The results were compared using ANOVA. There were no significant differences among the treatment groups with respect to maintenance infusion rate (7.8 +/- 1.8 micrograms/kg/min for Group 1, 7.7 +/- 2.5 micrograms/kg/min for Group 2, and 7.3 +/- 2.3 micrograms/kg/min for Group 3) or neostigmine-accelerated recovery interval of 25% to 75% (4.5 +/- 2.3 minutes, 4.4 +/- 3.1 minutes, 6.6 +/- 3.9 minutes in Groups 1, 2, and 3, respectively). The log dose-response data for Groups 1, 2, and 3 did not differ significantly (p = 0.068), and the calculated ED95 in each treatment group demonstrated no dose-related change (0.254 +/- 0.022, 0.279 +/- 0.033, and 0.240 +/- 0.022 for Groups 1, 2, and 3, respectively).

CONCLUSIONS

Ondansetron is an antiemetic drug that can be used in the perioperative period without concern for potentiation of nondepolarizing neuromuscular blockade, change in atracurium maintenance dose, or change in rate of neostigmine-induced recovery from neuromuscular blockade with atracurium.

Involvement of free radicals in cisplatin-induced emesis in Suncus murinus

The participation of free radicals in cisplatin-induced emesis was investigated in the house musk shrew, Suncus murinus. Thiobarbituric acid (TBA) values, which indicate the degree of lipid peroxidation, in brain, liver and small intestine were increased significantly 60 min after the treatment with cisplatin (20 mg/kg, i.p.). Moreover, cisplatin (20 mg/kg, i.p.)-induced emesis was prevented by intraperitoneal injection of N-(2-mercaptopropionyl)glycine (MPG), a radical scavenging agent, with ID50 value of 130 mg/kg. However, MPG did not block the emesis induced by copper sulfate (40 mg/kg, p.o.), veratrine (0.5 mg/kg, s.c.) or serotonin (10 mg/kg, i.p.). We also investigated the effects of superoxide dismutase conjugated to polyethylene glycol and catalase, but the number of vomiting episodes and latency did not change significantly when these agents were intraperitoneally injected 30 min prior to or 20 min after the administration of cisplatin. MPG did not affect the antitumor effect of cisplatin tested in vitro. These results suggest that free radicals mediate emesis caused by cisplatin and that radical scavengers may become a new class of prophylactic drug against cancer-chemotherapeutic drug-induced emesis.

Comparison of intermittent ondansetron versus continuous infusion metoclopramide used with standard combination antiemetics in control of acute nausea induced by cisplatin chemotherapy

BACKGROUND

Ondansetron is a serotonin antagonist that recently has been introduced as a preventive agent for chemotherapy-induced nausea and vomiting. The current study was performed to determine the degree of antiemetic control of ondansetron in combination with dexamethasone and lorazepam, and to compare this combination to the previously very effective regimen of lorazepam, dexamethasone, diphenhydramine, and continuous-infusion metoclopramide.

METHODS

Eighty chemotherapy-naive patients with newly diagnosed neoplasms undergoing cisplatin combination chemotherapy were randomized to receive one of two combination antiemetic regimens: lorazepam, dexamethasone, intermittent intravenous ondansetron; or lorazepam, dexamethasone, continuous-infusion metoclopramide, and diphenhydramine.

RESULTS

There was major control (0-1 episodes) of acute nausea-vomiting in all of the patients receiving the ondansetron combination antiemetic regimen, which was significantly better (P < 0.05) than the major control of the acute nausea-vomiting of the patients receiving the metoclopramide combination antiemetic regimen. The ondansetron-treated patients experienced only a mild headache as their only toxicity and had significantly (P 0.0026) less diarrhea, akathisia, and acute dystonic reactions than the patients receiving the metoclopramide regimen. Delayed nausea was controlled with prophylactic prochlorperazine.

CONCLUSIONS

The ondansetron regimen was more effective and less toxic, but its cost was 20 times more than the metoclopramide regimen.

Repeated use of granisetron in patients receiving cytostatic agents

BACKGROUND

Granisetron was shown to be a safe and effective antiemetic agent when given with initial cytostatic therapy. This study was undertaken to investigate the efficacy and safety of the continued use of granisetron.

METHODS

Ninety-one patients were given 438 cycles of granisetron during subsequent courses of cytostatic treatment. In 56 patients, 40 micrograms/kg i.v. was given in 159 cycles, and in 42 patients, 3 mg i.v. was given in 279 cycles. In patients having breakthrough symptoms, as many as two rescue doses were given to re-establish control.

RESULTS

Overall objective control of nausea and vomiting was observed in 88.6% of the 40 micrograms/kg-cycles and in 90.32% of the 3-mg cycles. In the 438 cycles given, complete control was achieved in 105 of 159 (66%) of the 40-micrograms/kg cycles and in 217 of 279 (77.78%) of the 3-mg cycles. Thirty-three patients received 97 cycles of cisplatin-based regimens. The objective control rate was 82.47% (80 of 97 cycles) in these patients. The control rate in patients receiving regimens not containing cisplatin was 94.4% (322 of 341 cycles). Rescue doses improved or resolved symptoms in 53 of 61 (86.9%) cycles. No statistically significant difference in nausea and vomiting control was seen between men and women or between the different age groups. The only toxicities encountered were headache in 14 of 438 (3.2%) cycles and mild constipation in 8 of 438 (1.8%) cycles.

CONCLUSION

Granisetron is safe and well tolerated, maintains its antiemetic efficacy after repeated cycles of therapy, and is effective as an interventional treatment for nausea and vomiting.

Ondansetron versus chlorpromazine for preventing emesis in bone marrow transplant recipients: a double-blind randomized study

Ondansetron, a selective 5-HT3 antagonist, is known to be effective for preventing emesis induced by cisplatin and other antineoplastic agents. We undertook a randomized double-blind study in a series of bone marrow transplantation (BMT) recipients to assess the antiemetic efficacy and the safety of ondansetron in comparison with chlorpromazine, which was being used at our institution, as the standard antiemetic agent for the conditioning regimen. Forty patients submitted to BMT (21 autologous, 19 allogeneic) were included in the study. Patients were randomly assigned to receive ondansetron (as a loading dose of 8 mg iv one hour before the beginning of the conditioning regimen followed by a continuous infusion of 1 mg per hour for the whole treatment period) or chlorpromazine 60 mg/m2/day given by continuous infusion for the same period (maximum 8 days). Twenty patients were assigned to ondansetron, while 20 were assigned to chlorpromazine. The response rate in terms of antiemetic efficacy and in nausea control was similar between the two treatment groups. On the contrary the two groups differed significantly in regard to side-effects: patients receiving ondansetron experienced significantly less sedation (p = 0.002), the absence of extrapyramidal reactions (p < 0.001) and no need for dose reduction (p < 0.001) as compared with patients treated with chlorpromazine.

Cisplatinum based chemotherapy: role of the antiserotoninergic ondansetron in prevention of emesis

Serotonin is a neurotransmitter involved in chemotherapy-induced emesis and ondansetron is a new drug endowed with selective antagonism against the 5HT3 receptors. Phase I-II studies have demonstrated its activity against acute emesis after single-dose cisplatin, reporting particularly low toxicity; in comparative studies with high-dose metoclopramide, it has been proved to be more effective and completely devoid of extrapyramidal side effects. Ondansetron has shown its activity and safety also in multiple-day cisplatin regimens. Its antiemetic efficacy is improved by the addition of dexamethasone. Preliminary data suggest its role also when used in single-dose administration. Its activity in the delayed phase of cisplatin emesis needs to be further explored.

Hepatotoxicity associated with cisplatin chemotherapy

OBJECTIVE

To report a case of possible cisplatin-associated hepatotoxicity.

CASE SUMMARY

A 69-year-old man received three cycles of cisplatin (100 mg/m2) and fluorouracil (1000 mg/m2/d for five days) for management of squamous cell carcinoma of the head and neck. Liver enzyme concentrations were within normal limits prior to each cycle of therapy but the aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, and lactate dehydrogenase concentrations increased on the second day of each cycle. The concentrations began to decline on day 3 of each course, despite continued fluorouracil administration, and returned to normal by day 10. The patient's antiemetic therapy included metoclopramide in cycle 1 and ondansetron in cycles 2 and 3, which may have contributed to the enzyme elevations.

DISCUSSION

Case reports of cisplatin-associated hepatotoxicity are reviewed. An association between cisplatin administration and hepatotoxicity is proposed in this patient.

CONCLUSIONS

This patient may have experienced cisplatin-induced liver damage. Metoclopramide and ondansetron may have contributed to this effect.

Ondansetron

Ondansetron is the first selective antagonist of the 5-hydroxytryptamine receptors (type 3) marketed for the prevention of emesis induced by antineoplastic agents. Ondansetron has been shown to be more active and less toxic than high-dose metoclopramide in patients submitted to cisplatin chemotherapy. Furthermore, when dexamethasone was added to ondansetron, its antiemetic efficacy increased significantly. In the prevention of emesis induced by a high single dose of cisplatin or by repeated low doses, ondansetron combined with dexamethasone has been shown to be the more efficacious and less toxic antiemetic treatment. However, in the prevention of delayed emesis from cisplatin, its role is still to be defined. In patients submitted to moderately emetogenic chemotherapeutic agents, ondansetron has shown an efficacy superior or equal to standard doses of metoclopramide, but is less toxic. Moreover, when compared with dexamethasone, its antiemetic efficacy and tolerability is similar; in this group of patients ondansetron should be used only when steroids fail. Ondansetron toxicity is generally mild; in particular, it does not induce extrapyramidal reactions. The most frequent side-effects are headache and constipation.

Phase III double-blind comparison of intravenous ondansetron and metoclopramide as antiemetic therapy for patients receiving multiple-day cisplatin-based chemotherapy

BACKGROUND

Ondansetron hydrochloride is a selective serotonin subtype 3 (5HT3) receptor antagonist that has been shown to be an effective antiemetic in patients receiving cisplatin chemotherapy.

METHODS

This double-blind study compared the safety and efficacy of intravenous ondansetron with metoclopramide in patients receiving a 4- or 5-day regimen of cisplatin (20-40 mg/m2/day) combination chemotherapy. Forty-five patients were enrolled, and efficacy of the drug therapy could be studied for all 45. Patients were randomly assigned (1:1) to receive three daily intravenous doses of either 0.15 mg/kg ondansetron or 1 mg/kg metoclopramide. All patients were monitored daily for the number of emetic episodes (vomiting or retching), severity of nausea, adverse events, and laboratory safety parameters.

RESULTS

Seven (30%) patients who received ondansetron had no emetic episodes throughout the entire study period compared with two (9%) who received metoclopramide (P = 0.077). The greatest difference in antiemetic efficacy was seen on day 1, when 18 (78%) patients who received ondansetron had no emetic episodes compared with 3 (14%) patients who received metoclopramide (P < 0.001). Significantly fewer antiemetic treatment failures (more than five emetic episodes or withdrawal from the study) occurred with patients given ondansetron (9%) than with those given metoclopramide (50%) during the entire study period (P = 0.002). The most commonly reported adverse event associated with ondansetron therapy was headache (controlled with acetaminophen), whereas diarrhea and restlessness were the most commonly reported adverse events associated with metoclopramide therapy. Extrapyramidal symptoms were judged to have occurred in 13 patients who received metoclopramide and 1 patient who received ondansetron. However, the patient who received ondansetron subsequently was judged to have had an anxiety attack. In patients with low or normal baseline transaminase values, a greater percentage who received ondansetron had transient increases as great as twice the upper limit of normal in aspartate transaminase (5% versus 0%) and alanine transaminase (17% versus 6%) than those who received metoclopramide.

CONCLUSIONS

Ondansetron is superior to metoclopramide as antiemetic therapy for multiple-day cisplatin-based chemotherapy.

Advances in the control of chemotherapy-induced emesis

Cancer patients consistently rank nausea and vomiting as the most feared side effects of treatment. Cisplatin, one of the most active chemotherapeutic agents, causes acute emesis and a delayed emesis syndrome, which also results in considerable patient morbidity. Despite the use of metoclopramide-containing combination regimens, approximately one third of cisplatin-treated patients continue to experience emesis. In recent years, considerable progress has been made in managing chemotherapy-induced emesis. This review discusses several factors that have contributed to improved antiemetic control, including standardization of antiemetic trial methodology, insight into the pathogenesis of chemotherapy-induced emesis, and the development of a new class of antiemetic agents, the serotonin antagonists. In clinical studies performed to date, these agents have generally proven to be both effective and safe. Three multicenter trials of the selective serotonin antagonist ondansetron in the prevention of nausea and vomiting from cisplatin are reviewed.

Current research in side effects of high-dose chemotherapy

The toxicities of chemotherapy continue to hamper dose escalation of specific chemotherapeutic agents. The impact of dose intensification upon survival will be assessed as clinical studies continue. Strategies to support chemotherapy dose intensification include BMT, use of CSFs and antiemetic drug combinations. Advances in symptom management will hopefully enhance quality of life for patients, whereas the development of chemoprotectant agents may allow specific organ toxicities to be avoided.

Effects of prolonged exposure to cisplatin on cytotoxicity and intracellular drug concentration

The present study was designed to analyse the cytotoxic effect of cisplatin in vitro as a function of various exposure times (up to 120 h), keeping constant the parameter C x T (product of the drug concentration per time). Intracellular drug concentrations were measured in parallel following analysis of cisplatin influx and efflux characteristics. A head and neck cancer cell line was selected to represent the spectrum of cisplatin antitumour activity. The IC50 values (micrograms/ml) for 1, 2, 11 and 121 h were, respectively 4.51, 2.73, 0.27 and 0.151. Reduction of the IC50 was clearly not linearly related to prolongation of the cisplatin exposure time. The kinetics of cisplatin incorporation into CAL 27 cells was investigated as a function of different cisplatin concentrations. A plateau was reached after 16 h of contact. For the extracellular cisplatin concentrations of 1, 2.5, 5 and 10 micrograms/ml, the average intracellular Pt concentrations at the plateau were, respectively (ng/10(6) cells): [mean (S.D.)] 12.8 (0.98), 31.11 (5.12), 71.38 (6.03) and 136.7 (16.5). Intracellular Pt concentrations were linearly related to the extracellular drug concentration (r = 0.99). The drug left the cells following a two-slope kinetics pattern with an alpha half-life of 1.29 h and a beta half-life of 94.4 h. The cytotoxic effect for a given C x T clearly differed for the different cisplatin exposure times. The longest exposure time (121 h) gave the least pronounced cytotoxicity. The intracellular Pt concentrations were linearly related to the C x T values. Cisplatin levels were much lower after the 121 h exposure. These data may prove valuable in establishing a rationale which can aid in selection of optimal modes of clinical cisplatin administration.

Are granisetron and ondansetron equivalent in the clinic?

There are no published direct trials of granisetron vs. ondansetron. Difficulties exist in comparing reported trials because of differences in methodology, especially in response criteria. In this review, a comparison is made between ondansetron and granisetron by recalculating the complete response criterion for granisetron, standardising it against that in the ondansetron programme (i.e. no vomiting). Weighted means have been calculated for three areas of study. Against cisplatin-induced emesis the (weighted) mean percentage of complete responders were calculated at 64% (range 49-77%) for granisetron and 49% (range 40-55%) for ondansetron. Against moderately emetogenic stimuli, the response rates were 76% (range 68-80%) and 73% (range 60-87%) respectively. For fractionated chemotherapy the response rates were 57% and 27% for granisetron and ondansetron respectively. Although not shown by formal statistical analysis, these results suggest that a clinical advantage for granisetron may exist.

In vitro release and tissue levels of ileal serotonin after cisplatin-induced emesis in the cat

We have studied the peripheral mechanisms responsible for the severe vomiting observed in cisplatin treated cats. Release of 5-hydroxytryptamine from isolated portions of the ileum and ileal tissue concentrations of 5-hydroxytryptamine were studied in vitro with control animals and animals previously treated with cisplatin. In the latter, two groups were observed: animals in which cisplatin (single dose, 10 mg/kg) induced vomiting within 4 h and animals that did not vomit within 4 h. Spectrofluorimetric assessment of 5-hydroxytryptamine in the perfusate and ileal tissue revealed that cisplatin increases both release, and tissue levels, of ileal 5-hydroxytryptamine in animals which vomited, whereas only ileal 5-hydroxytryptamine release was increased in animals which did not vomit. This may have clinical implications as cisplatin induced emesis may be more effectively prevented by drugs preventing ileal 5-hydroxytryptamine formation rather than release.

Recent clinical experience with dronabinol

Dronabinol, delta-9-tetrahydrocannabinol in sesame oil, has been used for several years as an antiemetic for patients receiving cancer chemotherapy. In combination studies with prochlorperazine, enhancement of efficacy, as measured by duration of episodes of nausea and vomiting and by severity of nausea, has been found. The incidence of psychotropic effects from dronabinol appears to be decreased by concomitant administration of prochlorperazine. In open pilot studies, dronabinol caused weight gain in seven of ten patients with symptomatic HIV infection. In both HIV and cancer patients, dronabinol improved appetite at a dose which was well tolerated for chronic administration.

Controlling cancer chemotherapy-induced emesis. An update

Cytotoxic chemotherapy can induce acute, delayed and anticipatory nausea and vomiting. The efficacy and toxicity data of the available anti-emetics and their role in chemotherapy-induced emesis are reviewed. Moreover, some pitfalls in the methodology of anti-emetic trials as well as factors known to affect the individual sensitivity of patients for the emetic challenge are illustrated. So far, high-dose metoclopramide (3-6 mg.kg-1.d-1) was the most effective single agent in the control of acute emesis. However, extrapyramidal reactions caused by its dopamine antagonism remained a major drawback. The addition of dexamethasone and/or lorazepam decreases the incidence of extrapyramidal reactions, and further improves anti-emetic control. In animals, serotonin type 3 receptor antagonists have demonstrated promising anti-emetic results against chemotherapy-induced and radiotherapy-induced emesis; the results of clinical studies are awaited. Delayed nausea and vomiting have not been studied as extensively. At present, the combination of metoclopramide and dexamethasone offers an optimal protection in approximately 50% of patients on cisplatin chemotherapy. Anticipatory nausea and emesis remain major problems, and an effective pharmacological treatment is lacking. Attempts to control this type of emesis focus on drugs with amnesic properties and on behaviour therapy.

Phase II study of echinomycin in patients with advanced breast cancer: a report of Cancer and Leukemia Group B protocol 8641

Twenty-five women with advanced histologically documented stage IV recurrent or inoperable breast cancer were enrolled on a phase II study of echinomycin administered at a dose of 1.2 mg/m2 intravenously over 30 minutes weekly for 4 weeks followed by a two week rest period. Seventy-six percent of patients had visceral dominant disease at study entry and all patients had previously received chemotherapy. One of 21 eligible patients had a partial response lasting 147 days. The median survival for this group of patients was 5.9 months and the median time to treatment failure was 1.7 months. Nausea and vomiting was the primary toxic effect and was severe or life-threatening in 43% of patients. Transient elevation of liver enzymes occurred in 30% of patients. Bone marrow suppression was not significant. Echinomycin as employed in this study did not demonstrate significant antitumor activity in previously treated patients with advanced breast cancer.

Reduction of carboplatin induced emesis by ondansetron

Ondansetron is a selective 5-HT3 antagonist with significant antiemetic properties in patients receiving cytotoxic chemotherapy. Patients who had suffered severe vomiting on carboplatin alone (23 patients with ovarian carcinoma) or in combination (two patients with testicular cancer) despite intensive antiemetic regimens were treated with ondansetron, given as 8 mg immediately prior to carboplatin followed by 8 mg orally, 8 hourly for 5 days. Twenty-five patients received 58 courses of ondansetron. In the first 24 h after the first course of chemotherapy with ondansetron, 17 patients (68%) experienced no vomiting, five patients (20%) had almost complete control and the other three patients had partial control. During the subsequent 4 days slightly lesser control was achieved. Nausea was similarly controlled in most patients. Twenty-two patients stated a preference for ondansetron with future chemotherapy. Fourteen patients received additional chemotherapy with ondansetron and in only three patients did the efficacy of therapy lessen. Toxicity was mild and transient with headache and constipation predominant. No extrapyramidal reaction was seen. Sedation was absent. Ondansetron is highly effective in refractory vomiting associated with carboplatin chemotherapy. It may be particularly beneficial when an extrapyramidal reaction has occurred on previous antiemetics and when sedation is unacceptable.