Review of the preclinical pharmacology and comparative efficacy of 5-hydroxytryptamine-3 receptor antagonists for chemotherapy-induced emesis

PURPOSE: This analysis was undertaken to review published reports of the comparative efficacy and safety of 5-hydroxytryptamine-3 (5-HT3) receptor antagonists in the prophylaxis of acute chemotherapy-induced emesis. METHODS: Comparison data used are the preclinical pharmacology as well as the design and results of clinical trials. Seven comparative studies that used granisetron, ondansetron, or tropisetron in patients who received either moderately or highly emetogenic chemotherapy are reviewed. As the study designs, patient population, chemotherapy, antiemetic doses and schedule, and methods of assessment were slightly different, the results of each study are analyzed independently. Effectiveness is assessed by emetic episodes, nausea, and patient preference. RESULTS: The preclinical pharmacologic profile is different among the 5-HT3 antagonists in terms of potency, selectivity, dose response, and duration of action. The comparative clinical trials show that a single intravenous (i.v.) dose of granisetron 3 mg is as effective as multiple (8 mg x 3) or single (32 mg) i.v. doses of ondansetron for the prevention of acute nausea and emesis due to cisplatin. In the two moderately emetogenic clinical trials, granisetron 3 mg i.v. was at least as effective as ondansetron 8 mg i.v. +/- 24 mg orally and tropisetron 5 mg i.v. Patient preference was evaluated in three of the four crossover trials: granisetron was preferred in three of four, and no preference was reported in the fourth. The one trial to compare ondansetron 0.15 mg/kg x 3 versus granisetron 10 micrograms/kg x 1 or granisetron 40 micrograms/kg i.v. demonstrated equivalent control of nausea and vomiting in patients who received cisplatin-based chemotherapy. CONCLUSION: The 5-HT3 receptor antagonists compared are highly effective antiemetic agents that have now become the standard of care for preventing chemotherapy-induced emesis. Whether the described preclinical differences among these agents are also clinically significant remains to be seen. In the comparative trials analyzed, the 5-HT3 receptor antagonists demonstrated relatively equivalent clinical efficacy. Cost analysis may favor the use of one agent over another depending on the emetogenic challenge, dose of the 5-HT3 antagonists, and number of doses recommended. Patient preference may be an important factor to be considered in future antiemetic trials.     

High-dose epirubicin is not an alternative to standard-dose doxorubicin in the treatment of advanced soft tissue sarcomas. A study of the EORTC soft tissue and bone sarcoma group

The activity and toxicity of single-agent standard-dose doxorubicin were compared with that of two schedules of high-dose epirubicin. A total of 334 chemonaive patients with histologically confirmed advanced soft-tissue sarcomas received (A) doxorubicin 75 mg m(-2) on day 1 (112 patients), (B) epirubicin 150 mg m(-2) on day 1 (111 patients) or (C) epirubicin 50 mg m(-2) day(-1) on days 1, 2 and 3 (111 patients); all given as bolus injection at 3-week intervals. A median of four treatment cycles was given. Median age was 52 years (19-70 years) and performance score 1 (0-2). Of 314 evaluable patients, 45 (14%) had an objective tumour response (eight complete response, 35 partial response). There were no differences among the three groups. Median time to progression for groups A, B and C was 16, 14 and 12 weeks, and median survival 45, 47 and 45 weeks respectively. Neither progression-free (P = 0.93) nor overall survival (P = 0.89) differed among the three groups. After the first cycle of therapy, two patients died of infection and one owing to cardiovascular disease, all on epirubicin. Both dose schedules of epirubicin were more myelotoxic than doxorubicin. Cardiotoxicity (> or = grade 3) occurred in 1%, 0% and 2% respectively. Regardless of the schedule, high-dose epirubicin is not a preferred alternative to standard-dose doxorubicin in the treatment of patients with advanced soft-tissue sarcomas.     

Greater antitumor efficacy of paclitaxel administered before epirubicin in a mouse mammary carcinoma

Combined treatment with paclitaxel and anthracyclines is increasingly being tested in clinical practice. Epirubicin is in general administered before paclitaxel. We have investigated, using a murine mammary adenocarcinoma, whether the efficacy and toxicity of this combination is influenced by treatment sequence, different time intervals and dose intensity. The tumor was transplanted into the right hind foot of C3D2F1 female mice. Paclitaxel was administered i.p. in doses ranging from 15 mg/kg to 75 mg/kg and epirubicin (i.p. or i.v.) in doses from 9 mg/kg to 30 mg/kg. The hepatic and peritoneal toxicity observed with epirubicin administration increased in combined treatments (stronger with i.p. than i.v. epirubicin administrations) and was dose-dependent. When paclitaxel and epirubicin were administered simultaneously or paclitaxel was given 24 h before epirubicin, the same tumor growth delays were obtained in all groups. A smaller effect was observed when paclitaxel was administered 24 h after epirubicin. Increasing the epirubicin or paclitaxel dose led to higher tumor growth delays but also an increased toxicity. In conclusion, in this experimental model, the administration of 45 mg/kg paclitaxel before 15 mg/kg epirubicin was very effective and the increased toxicity can be limited by introducing an interval of 24 h between drug administrations. These results should be considered when designing clinical trials.     

Stability and compatibility of granisetron hydrochloride in i.v. solutions and oral liquids and during simulated Y-site injection with selected drugs

The stability and compatibility of granisetron hydrochloride in common i.v. fluids and oral liquids and during simulated Y-site injection with selected drugs were studied. One milliliter of solution containing granisetron 1 mg (as the hydrochloride salt) was added to 50 mL of 5% dextrose injection, 5% dextrose and 0.9% sodium chloride injection, 5% dextrose and 0.45% sodium chloride injection, or 0.9% sodium chloride injection in polyvinyl chloride (PVC) bags and to 5 mL of 5% dextrose injection, 0.9% sodium chloride injection, or bacteriostatic water for injection in polypropylene syringes and stored at room temperature (20 degrees C) for 24 hours. One milliliter of the granisetron hydrochloride injection was added to 50 mL of apple juice, orange juice, cola, or an electrolyte replacement solution and stored for 60 minutes at room temperature. Twenty-nine drugs were mixed with the granisetron hydrochloride injection in 0.9% sodium chloride injection in volumes simulating Y-site injection and stored at room temperature. Finally, dexamethasone sodium phosphate injection 0.5 mL and 1 mL of the granisetron hydrochloride injection were added to 50 mL of 0.9% sodium chloride injection in a PVC bag and stored for 60 minutes. Drug concentrations were determined by high-performance liquid chromatography, and color, clarity, and pH were evaluated. Granisetron hydrochloride was stable in and compatible with all the i.v. solutions and oral liquids. Neither granisetron nor any of the drugs it was tested with during simulated Y-site injection showed any physical changes except for a slight Tyndall effect in the granisetron hydrochloride-doxorubicin hydrochloride combination; all the drugs retained at least 96% of initial concentrations. Granisetron and dexamethasone sodium phosphate were stable and compatible in the admixture. Granisetron 1 mg (as the hydrochloride salt) was stable for 24 hours in four i.v. infusion fluids in PVC bags and in 5% dextrose injection, 0.9% sodium chloride injection, and bacteriostatic water for injection in polypropylene syringes; for 1 hour in four oral liquids; for 4 hours in the presence of each of 29 drugs during simulated Y-site injection; and for 1 hour when mixed with dexamethasone sodium phosphate in 0.9% sodium chloride injection in a PVC bag.     

Intravenous dolasetron mesilate in the prevention of postoperative nausea and vomiting in females undergoing gynecological surgery

STUDY OBJECTIVE: To evaluate a range of doses of intravenous (i.v.) dolasetron mesilate, in preventing postoperative nausea and vomiting (PONV). DESIGN: Double-blind, placebo-controlled, randomized, multicenter trial. SETTING: Ten hospitals and/or surgical centers. PATIENTS: 281 women undergoing gynecologic surgery with general anesthesia. INTERVENTIONS: Patients received one of four single, i.v. doses of dolasetron mesilate (12.5 mg, 25 mg, 50 mg, and 100 mg) or placebo administered following cessation of anesthesia. MEASUREMENTS AND MAIN RESULTS: Patients were monitored for 24 hours following study drug administration. The antiemetic efficacy of each dolasetron mesilate dose was evaluated by recording the number and timing of emetic episodes, and the effects on nausea were assessed by use of visual analog scales (VAS). Safety was assessed by adverse event reports, clinical laboratory tests, electrocardiographic (ECG) measurements, and monitoring vital signs. Complete responses (patients with no emetic episodes and no escape antiemetic medication requirements in 24 hours) were achieved by 54% in the 12.5-mg, 67% in the 25-mg, and 59% in both the 50-mg and 100-mg dolasetron mesilate dose groups, and by 43% in the placebo group. Nausea VAS assessments demonstrated that dolasetron-treated patients were significantly (p = 0.048) more likely to report no nausea (VAS score < 5 mm) than those in the placebo group. Adverse events reported generally were mild in intensity, and there were no clinically significant changes in laboratory tests, vital signs, or ECG parameters. CONCLUSIONS: Dolasetron was effective and well tolerated for the prevention of PONV in female patients undergoing gynecologic surgery with general anesthesia.     

A double-blind, placebo-controlled, dose-ranging safety evaluation of single-dose intravenous dolasetron in healthy male volunteers

The safety and tolerability of dolasetron mesylate, a potent and selective 5-HT3 receptor antagonist, were evaluated after single intravenous doses in healthy male volunteers. In this double-blind, placebo-controlled, randomized, phase I study, 80 subjects received either placebo or dolasetron in escalating doses (0.6 to 5.0 mg/k). Subjects were monitored for adverse events, vital sign and laboratory alterations, and changes in electrocardiographic (ECG) intervals and electroencephalographic (EEG) patterns. Overall, the percentage of subjects reporting adverse events was similar in those receiving dolasetron (44/64; 68.8%) or placebo (10/16; 62.5%); most adverse events were mild in severity. Subjects receiving dolasetron reported a higher incidence of central nervous system (headache and dizziness/lightheadedness), gastrointestinal (increased appetite and nausea), and visual adverse events and taste alterations. No clinically significant changes in laboratory variables were observed. Transient and asymptomatic ECG changes (small mean increases in PR interval and QRS complex duration versus baseline) were noted in several subjects at 1 to 2 hours after infusion at doses > or = 3.0 mg/kg. Transient, mild blood pressure decreases were observed in five subjects, including one on placebo. Dolastron mesylate was well tolerated in single intravenous doses up to 5.0 mg/kg in healthy male volunteers. Clinical studies of the drug are ongoing for antiemetic indications.     

Paclitaxel with mitoxantrone, fluorouracil, and high-dose leucovorin in the treatment of metastatic breast cancer: a phase II trial

PURPOSE: Paclitaxel is a highly active single agent in the treatment of breast cancer. However, its optimal incorporation into combination regimens awaits definition. In this phase II study, we added paclitaxel, administered by 1-hour infusion, to a previously described combination regimen that included mitoxantrone, fluorouracil (5-FU), and high-dose leucovorin (NFL). PATIENTS AND METHODS: Forty-six patients with metastatic breast cancer received the following regimen as first- or second-line treatment: paclitaxel 135 mg/m2 by 1-hour intravenous (i.v.) infusion on day 1, mitoxantrone 10 mg/m2 by i.v. bolus on day 1, 5-FU 350 mg2/m by i.v. bolus on days 1, 2, and 3, and leucovorin 300 mg i.v. over 30 to 60 minutes immediately preceding 5-FU on days 1, 2, and 3. Courses were administered at 3-week intervals for a total of eight courses in responding patients. RESULTS: Twenty-three of 45 assessable patients (51%) had major responses. Previous chemotherapy, and in particular previous treatment with doxorubicin, did not affect response rate. The median response duration was 7.5 months. Myelosuppression was moderately severe, with 76% of courses resulting in grade 3 or 4 leukopenia. Hospitalization for treatment of fever during neutropenia was required in 13% of courses, and two patients died as a result of sepsis. Two patients developed severe congestive heart failure after a large cumulative anthracycline dose. CONCLUSION: This combination regimen was active as first- or second-line therapy for metastatic breast cancer, although its activity compared with other combination regimens or with paclitaxel alone is unclear. Myelosuppression was more severe than anticipated based on previous results with the NFL regimen or with paclitaxel administered at this dose and schedule as a single agent. The infrequent development of cardiotoxicity in these patients suggests that the paclitaxel/mitoxantrone combination may not share the problems previously reported with the paclitaxel/doxorubicin combination.     

Etoposide, epirubicin and cisplatin (EEP) combination in metastatic cancers of the cardia and the stomach. Groupe de recherche en cancérologie du Nord (GRECNO)

This study was aimed to confirm the therapeutic activity of the combination of etoposide, doxorubicin and cisplatin which has shown some clinical efficiency as first line therapy in advanced gastric cancer. Seventeen patients with metastatic gastric cancer were treated with etoposide (120 mg/m2, i.v., on day 5, 6 and 7), epirubicin (20 mg/m2, i.v., on day 1 and 7) and cisplatin (40 mg/m2, i.v., on day 2 and 8), q 4 weeks. In 16 patients evaluable for response, three (19%) obtained a partial response lasting from 93 to 360 days. Fifteen patients were evaluable for toxicity. Main toxicities > grade 2 included anemia (2/15), neutropenia (5/15), alopecia (8/15), fatigue (3/15), diarrhea (2/15), vomiting (2/15). Twenty nine per cent of severe toxic events were documented all along 52 cycles. Therefore we failed to confirm that this regimen could be of clinical efficiency in advanced gastric cancer as regards the benefits/toxicity ratio.     

Granisetron reduces the incidence of nausea and vomiting after middle ear surgery

We studied the efficacy of granisetron, a selective 5-hydroxytryptamine type-3 receptor antagonist, in preventing postoperative nausea and vomiting (PONV) after middle ear surgery. In a randomized, double-blind, placebo-controlled study, 60 ASA I patients received placebo (saline) or granisetron 40 micrograms kg-1 i.v. immediately before induction of anaesthesia (n = 30 in each group). A standard general anaesthetic technique was used. During the first 24 h after anaesthesia, the incidence of PONV in patients who had received granisetron was lower than in those who had received placebo (17% vs 63%; P < 0.05). There were no clinically important adverse effects in either group. We conclude that granisetron, given before anaesthesia, reduced the incidence of PONV after middle ear surgery.     

Monohydroxyethylrutoside, a dose-dependent cardioprotective agent, does not affect the antitumor activity of doxorubicin

The cumulative dose-related cardiotoxicity of doxorubicin is believed to be caused by the production of oxygen- free radicals. 7-Monohydroxyethylrutoside (monoHER), a semisynthetic flavonoid and powerful antioxidant, was investigated with respect to the prevention of doxorubicin-induced cardiotoxicity in mice and to its influence on the antitumor activity of doxorubicin in vitro and in vivo. Non-tumor-bearing mice were equipped with a telemeter in the peritoneal cavity. They were given six weekly doses of 4 mg/kg doxorubicin i.v., alone or in combination with either 100 or 250 mg/kg monoHER i.p., 1 h prior to doxorubicin administration and for the following 4 days. Cardiotoxic effects were measured from electrocardiogram changes up to 2 weeks after treatment. Protection against cardiotoxicity was found to be dose dependent, with 53 and 75% protection, respectively, as calculated from the reduction in the increase in the ST interval. MonoHER and several other flavonoids with good antioxidant properties were tested for their antiproliferative effects in the absence or the presence of doxorubicin in A2780 and OVCAR-3 human ovarian cancer cells and MCF-7 human breast cancer cells in vitro. Some flavonoids were directly toxic at 50 and 100 microM, whereas others, including monoHER, did not influence the antiproliferative effects of doxorubicin at these concentrations. The influence of monoHER was further tested on the growth-inhibitory effect of 8 mg/kg doxorubicin i.v., given twice with an interval of 1 week in A2780 and OVCAR-3 cells that were grown as s.c. xenografts in nude mice. MonoHER, administered 1 h before doxorubicin in a dose schedule of 500 mg/kg i.p. 2 or 5 days per week, was not toxic and did not decrease the antitumor activity of doxorubicin. It can be concluded that monoHER showed a dose-dependent protection against chronic cardiotoxicity and did not influence the antitumor activity of doxorubicin in vitro or in vivo.     

Changes in electrocardiographic findings with aging in a longitudinal study of 500 apparently healthy persons aged 60 years and older

A number of studies have been published which have attempted to define the electrocardiographic (ECG) changes with aging, but most of them were obtained from cross-sectional studies. To distinguish ECG changes related to physiological aging from those associated with arteriosclerosis, we assessed the ECG changes of 500 apparently healthy subjects, aged 60 years and older in 1992, who had been followed at the Keio Health Consulting Center for over 15 years. All subjects had no overt cardiovascular diseases in 1992. We compared the ECG in 1992 with that taken over 15 years ago. Changes in ECG during that period were also reviewed. With aging, the mean axis deviated to the left, the mean QTc interval was shortened, and the mean PR interval was prolonged. ST segmental change, atrial overloading, bundle branch block developed newly in 16%, 8% and 7% of, respectively. There were no relationships among axis deviation, PR interval change, or QTc shortening and coronary risk factors. QTc prolongation and ST segmental change were strongly related to hypertension or impaired glucose tolerance. When ECG changes in those under 65 years old were compared with those over 80 years old, the incidence of ST segmental change in those over 80 years old was significant higher. This study was not a prospective study but suggested each type of ECG change related to aging was affected by physiological and/or pathological factors in a distinct way and had different phases of development and progression.     

Electrocardiographic effects of desipramine and 2-hydroxydesipramine in children, adolescents, and adults treated with desipramine

OBJECTIVE: To assess the developmental effects of desipramine (DMI) treatment on the electrocardiogram (ECG), we investigated serum concentrations of DMI ([DMI]), and its major active metabolite 2-hydroxydesipramine ([OHDMI]) and ECG parameters. METHODS: ECGs and [DMI] and [OHDMI] were analyzed from 50 children, 39 adolescents, and 30 adult psychiatric patients receiving DMI. RESULTS: There were modest overall correlations between [DMI], [OHDMI], or [OHDMI+DMI], and the PR and QRS intervals when data from all 119 subjects were pooled. Within the pediatric age groups there were no significant associations between serum drug levels and heart rate or conduction intervals; and in all subjects with ECG abnormalities, there were some findings of higher [DMI], [OHDMI], and [OHDMI+DMI]. CONCLUSIONS: These findings indicate that only modest associations of [DMI] and [OHDMI] with ECG conduction intervals were found, and are not likely to be clinically significant in any of the age groups studied. Compared with adults, children and adolescents do not appear to be at increased risks for ECG changes related to DMI treatment or to circulating concentrations of [DMI] or [OHDMI].     

Clinical and epidemiologic aspects of ankylosing spondylitis and spondyloarthropathies

In our previous randomized trial of advanced gastric cancer patients, the addition of epirubicin (EPI) to 5-fluorouracil (FU) with folinic acid (FA) resulted in an improved response rate and survival in the responder patients. Preclinical studies also showed an enhancement of FU and anthracyclines with interferon. To evaluate the possibility of human lymphoblastoid interferon (IFN) to enhance the therapeutic activity of the FA-FU + EPI combination regimen, 39 advanced gastric cancer patients received: FU at 375 mg/m2 i.v. immediately after FA (l-isomer form) at 100 mg/m2 i.v. for 5 consecutive days; EPI at 60 mg/m2 i.v. on day 1, and IFN 3 MU s.c. for 7 consecutive days, starting 2 days before the FA-FU administration. Thirty-seven patients were evaluable for response and toxicity. Twelve partial responses were observed with an overall response rate of 32% (95% CI, 17-48%). The median response duration was 6 months, and the median survival time was 8 months. Toxicity was mild and no grade 4 side effects or treatment-related deaths were observed. However, the addition of IFN to the FA-FU + EPI regimen did not improve response, duration of response or survival.     

ABILHAND: a Rasch-built measure of manual ability

BACKGROUND: Dexamethasone decreases chemotherapy-induced emesis when added to an antiemetic regimen. This study was undertaken to evaluate the efficacy of granisetron-dexamethasone combination for the prevention of postoperative nausea and vomiting (PONV) in female patients undergoing general anaesthesia for breast surgery. METHODS: In a randomized, double-blind manner, 135 ASA I patients, aged 40-65 years, were assigned to receive placebo (saline), granisetron 40 micrograms.kg-1 or granisetron 40 micrograms.kg-1 plus dexamethasone 8 mg i.v. (n = 45 of each) immediately before the induction of anaesthesia. A standard general anaesthetic technique and postoperative analgesia were used. The PONV and safety assessments were performed continuously during the first 3 h (0-3 h) and the next 21 h (3-24 h) after anaesthesia. RESULTS: A complete response, defined as no PONV and no administration of rescue antiemetic medication, during 0-3 h after anaesthesia was 51%, 82% and 96% in patients who had received placebo, granisetron and granisetron-dexamethasone combination, respectively; the corresponding incidence during 3-24 h after anaesthesia was 56%, 84% and 98% (P < 0.05; overall Fisher's exact probability test). No clinically important adverse events were observed in any of the groups. CONCLUSION: Prophylactic use of granisetron-dexamethasone combination is more effective than granisetron alone for the prevention of PONV after breast surgery.     

Randomized trial comparing two different modalities of administration of the same cytotoxic drugs in metastatic breast cancer

This protocol compare the efficacy of continuous infusion fluorouracil (5-FU) with weekly doxorubicin (DOX) and cyclophosphamide (CPM) to a "classical" monthly regimen of the same drugs, as a first line of treatment in metastatic breast carcinoma. The first arm of this protocol consisted of FAC: 5-FU 600 mg/m2 i.v. over 1 hour, day(d) 1, 2, 3, DOX 50 mg/m2 i.v. bolus, d1, and CPM, 400 mg/m2 i.v. bolus, d 1, 2, 3. The second arm consisted of FULON: 5-FU 250 mg/m2 per day continuously infused from d1 to d22, CPM 300 mg/m2 i.v. bolus, d1, 8, 15, 22, and DOX 15 mg/m2 i.v. bolus, day 1, 8, 15, 22. Between January 1990 and June 1993, 258 women with proven metastatic breast carcinoma were randomly assigned either to receive FAC or FULON chemotherapy regimen. Chemotherapy courses were administrated every 4 weeks for FAC regimen and every 6 weeks for FULON. Response rate (54 versus 53%), response duration (14 versus 12 months) and overall survival duration (23 versus 21 months) were not significantly different in the two regimens (FAC versus FULON). Preorative prognostic value of liver metastasis or high LDH level was slightly attenuated in patients treated by FULON. Efficacy of infusional 5-FU in metastatic breast cancer could have been lowered by weekly infusion of doxorubicin in the FULON regimen compared to monthly infusion. According to the modalities of delivery of the drugs, the two regimens seem equally effective.     

Independent autonomic modulation of the human sinus and AV nodes: evidence from beat-to-beat measurements of PR and PP intervals during sleep

INTRODUCTION: Evidence from animal experiments indicates that the autonomic nervous system may influence the sinus (SA) and atrioventricular (AV) nodes differently. We investigated, therefore, whether there are spontaneous functional differences in the innervation of the SA and AV nodes in man. METHODS AND RESULTS: This study was performed in 10 healthy males (ages 21 to 26 years) during strict bed rest from 10 pm to 6 am. Three ECG leads were digitized on-line. PR and PP intervals were determined on a beat-to-beat basis off-line using a correlation algorithm with an accuracy of +/- 2 msec and were verified visually. During major body movements, there were sudden decreases in PP intervals of 36 to 827 msec (mean 335) for periods of 6 to 265 seconds (mean 24). During these phases of heart rate (HR) acceleration, PR intervals showed either concomitant shortening (9 to 30 msec), no change, or lengthening (6 to 25 msec). Furthermore, tonic changes in the PR interval occurred over 15-minute periods during which the range of PP intervals was constant. Additionally, recovery-adjusted PR interval (PR-b2/RP) and cycle length were negatively correlated for some periods, which confirmed independent autonomic effects on SA node and AV node. CONCLUSION: Beat-to-beat measurement of PR intervals allows for evaluation of autonomic effects on the human AV node. The different patterns in PR intervals during sudden spontaneous increases in HR and the tonic changes in PR interval indicate that the autonomic inputs to the SA and AV nodes are, in principle, independent of each other.     

Variation in postantibiotic effect of clindamycin against clinical isolates of Staphylococcus aureus and implications for dosing of patients with osteomyelitis

Initial measurements of postantibiotic effect (PAE) were made by a standard laboratory method (exposure to 1 mg of clindamycin per liter for 1 h). The range of PAE for 21 strains of Staphylococcus aureus isolated from osteomyelitis patients was 0.4 to 3.9 h, which markedly exceeded the coefficient of variation for the method (6 to 19%). Exposure of S. aureus to three doses of clindamycin at 8-h intervals had no consistent effect on either PAE or MIC. The PAE was dependent on both concentration and duration of exposure to clindamycin: for example, the PAEs for one strain were 1.7 h after exposure to 1 mg/liter for 1 h, 2.4 h after exposure to 4 mg/liter for 1 h, and 5.9 h after exposure to 4 mg/liter for 3 h. Pharmacokinetic simulations showed that the dose required to maintain free serum clindamycin concentrations above the MIC was 300 mg 6 hourly after oral administration (95% confidence interval, 243 to 301 mg) and 1.2 g 6 hourly (95% confidence interval, 305 to 1,145 mg) after intravenous (i.v.) administration. The duration of PAE would have to be at least 2.4 h to allow an increase in the oral dose interval to 8 h or to allow i.v. administration of 300 mg 6 hourly. Additional PAE experiments were performed with the three strains for which PAEs are the shortest after exposure to 1 mg/liter for 1 h (0.4 to 1.2 h). The PAE for these three strains increased markedly to 4.4 to 6.7 h following exposure to 2 mg/liter for 6 h (to mimic the area under the concentration-time curve from 0 to 6 h after a 300-mg dose). These data suggest that oral clindamycin could be administered at 300 mg 8 hourly in the treatment of S. aureus infection, whereas the i.v. dose interval should be 6 h. These suggestions should be confirmed by performing clinical trials.     

Prophylactic oral antiemetics for preventing postoperative nausea and vomiting: granisetron versus domperidone

In this prospective, randomized, double-blinded study, we evaluated the efficacy of the oral antiemetics, granisetron and domperidone, for the prevention of postoperative nausea and vomiting (PONV) in 100 women undergoing major gynecologic surgery. Patients received either granisetron 2 mg or domperidone 20 mg (n = 50 in each group) orally 1 h before surgery. Standardized anesthetic techniques and postoperative analgesia regimens were used. Complete response (defined as no PONV and no administration of rescue antiemetic medication) for 0-3 h after anesthesia was 88% with granisetron and 52% with domperidone; the corresponding incidence for 3-24 h after anesthesia was 86% and 48% (P < 0.05). No clinically important adverse events due to the drugs were observed in any of the groups. In conclusion, the efficacy of preoperative oral granisetron is superior to that of domperidone for the prevention of PONV after major gynecologic surgery. IMPLICATIONS: We compared the efficacy of granisetron and domperidone administered orally for the prevention of postoperative nausea and vomiting in women undergoing gynecologic surgery. Preoperative oral granisetron was more effective than domperidone.     

Dolasetron. A review of its pharmacology and therapeutic potential in the management of nausea and vomiting induced by chemotherapy, radiotherapy or surgery

Dolasetron (dolasetron mesilate) is a pseudopelletierine-derived 5-HT3 antagonist which has recently become available for clinical use. It is rapidly converted in vivo to its active major metabolite, hydrodolasetron, which appears to be largely responsible for its pharmacological activity. In clinical trials, single intravenous or oral doses of dolasetron were effective in preventing acute chemotherapy-induced nausea and vomiting (CINV). Intravenous doses of 1.8 mg/kg achieved complete suppression of vomiting in approximately 50% of patients receiving highly emetogenic cisplatin-containing chemotherapy and in approximately 60 to 80% of patients receiving moderately emetogenic chemotherapy. In the latter setting, oral doses of 200 mg achieved similar response rates. In comparative studies, intravenous dolasetron 1.8 mg/kg was as effective as intravenous granisetron 3 mg or ondansetron 32 mg after highly emetogenic chemotherapy, and oral dolasetron 200 mg was equivalent to multiple oral doses of ondansetron (3 or 4 doses of 8 mg) after moderately emetogenic chemotherapy. Dolasetron 1.8 mg/kg was superior to metoclopramide in preventing emesis induced by high dose cisplatin or by moderately emetogenic chemotherapy in high risk subgroups. Dolasetron has also shown efficacy in preventing radiotherapy-induced nausea and vomiting (RINV) in preliminary studies. Single intravenous or oral dolasetron doses ranging from 12.5 to 100 mg and 25 to 200 mg, respectively, were significantly more effective than placebo in preventing postoperative nausea and vomiting (PONV) in female surgical patients. A 50 mg intravenous dose was as effective in preventing PONV as ondansetron 4 mg in a mixed-gender group. Intravenously administered dolasetron was also effective in treating established PONV, although complete suppression of vomiting was achieved in < 40% of patients. Dolasetron has a tolerability profile characteristic of this class of compounds, with headache, dizziness and diarrhoea being the most commonly occurring adverse events in clinical trials. Diarrhoea is not thought to be related to dolasetron administration, being experienced mostly by patients receiving chemotherapy. Dolasetron and other 5-HT3 receptor antagonists have been associated with minor changes in ECG intervals, but these generally do not appear to be clinically important. Thus, available evidence suggests that dolasetron will provide an alternative to other 5-HT3 receptor antagonists for the management of CINV and PONV. Further studies are required to determine whether it offers any advantages over other agents in these settings and to determine the optimum dosage for preventing RINV.     

Effect of prostaglandin A1 on proliferation and telomerase activity of human melanoma cells in vitro

BACKGROUND AND OBJECTIVE: Idarubicin, an anthracycline analogue, is active in non-Hodgkin's lymphoma. This study evaluates the efficacy and toxicity of a combination of idarubicin, etoposide and intermediate-dose cytarabine (IVA) in unfavorable lymphoma in relapse or resistant to prior doxorubicin- or novantrone-based regimens. DESIGN AND METHODS: Thirty patients with relapsing or resistant unfavorable lymphoma received a combination of idarubicin 12 mg/m2 i.v. on day 1, etoposide 60 mg/m2 i.v. every 12 hours for 3 days, and Ara-C 1 g/m2 i.v. every 12 hours for 3 days (3-hour infusion). Median age was 39 years (range: 22-60). All patients had been given prior doxorubicin or novantrone; 54% of them had received 2 or more chemotherapy regimens; 67% of total were in clinical relapse (30% in their second relapse), and 23% had resistant disease. RESULTS: The overall response rate to IVA was 60% (18 of 30 patients). Complete remission rate was 20% (6 of 30) in the whole group, 45% (5 of 11) among patients in their first relapse. Remission median duration was 9 months (range: 1-18), with a 3-year relapse-free and overall survival of 20% and 15%, respectively. Severe neutropenia occurred in 13 patients (43%) and severe thrombocytopenia in 11 patients (37%), with a median duration of 9 and 13 days, respectively. No cardiac toxicity developed; sepsis during neutropenia was documented in four instances and two patients (7%) died of therapy-related events (septic shock). INTERPRETATION AND CONCLUSIONS: Idarubicin combined with etoposide and intermediate-dose cytarabine proved to be an active salvage therapy in unfavorable lymphoma given prior doxorubicin or novantrone; the best results were obtained among patients in their first relapse, with low tumor burden.