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PubMed2004

Apical clearance rigid contact lenses induce corneal steepening.

PURPOSE: Anecdotal reports suggest that steeply fitted rigid contact lenses can induce corneal steepening and myopic shifts in refraction. This study investigated changes in corneal topography, corneal thickness, and refraction after short-term wear of apical clearance lenses. METHODS: : Ten young adults participated in the study in which apical clearance lenses (Conoid, Hydron Pty. Ltd., Frenchs Forest, NSW, Australia), fitted approximately 0.3 mm steeper than the flattest keratometric reading, were worn for 4 h. A polymethyl methacrylate (PMMA) lens was worn in one eye, and a Boston XO lens (Bausch & Lomb, Rochester, NY) was worn in the other. Lenses were nonfenestrated in the first trial, and a single midperipheral fenestration was incorporated for a second trial. Corneal topography was monitored using the EyeSys topographic analysis system (EyeSys Vision, Inc., Houston, TX); central corneal thickness was quantified using ultrasonic pachometry; and refraction and anterior ocular response were also monitored. RESULTS: Significant central corneal edema (8.2 +/- 2.2%) was demonstrated in the PMMA lens-wearing eye only. Fenestration did not reduce the edema response. We found significant corneal steepening over a 5- to 6-mm central zone, which was more pronounced in the PMMA lens-wearing eye and was modified by lens fenestration. The curvature changes altered central corneal shape from prolate (Q = -0.06 +/- 0.10) to oblate (Q = -0.26 +/- 0.31). A slight myopic shift in refraction (-0.38 +/- 0.60 D) was found with the PMMA lenses only. CONCLUSIONS: : Apical clearance lenses induce corneal steepening after short-term wear. Although corneal molding is implicated as the primary factor driving the shape change, corneal edema and postlens tear film pressures can modify this response.

Adult↗

PubMed1998

A multi-centre study of the effect of Mectizan treatment on onchocercal skin disease: clinical findings.

A multi-centre, double-blind, placebo-controlled trial of the effect of Mectizan (ivermectin, MSD) treatment on the skin disease and severe itching associated with onchocerciasis was carried out in the forest zones of Nigeria, Ghana and Uganda. Overall, 4072 subjects, none of whom had received Mectizan previously, were enrolled and allocated into four groups, to receive Mectizan every 3, 6 or 12 months or placebo every 3 months. Subjects with skin lesions were stratified within each treatment group to ensure equal representation. Each subject was given a clinical examination and interviewed on enrolment and then 3-monthly for 15 months. The presence and severity of itching were determined by open-ended questions followed by probing questions. Skin lesions were classified and their severity graded using a standard system. Analysis of the results was restricted to the data from the 1530 subjects who received all their scheduled treatments and attended all the follow-up visits. From 6 months onwards, all subjects who had received Mectizan reported less severe itching, had lower prevalences of reactive skin lesions and had less severe skin lesions than those in the placebo group (P < 0.05 for each). The greatest reductions, in both itching and skin disease, were seen in subjects treated with Mectizan every 6 months. Mectizan treatment is therefore beneficial for the control of troublesome itching and for reducing the prevalence and severity of skin disease causes by Onchocerca. it is recommended that mass distribution of Mectizan to communities in the study areas be carried out at 6-monthly intervals for maximum efficacy.

Africa↗

PubMed1996

Effects of artemisinin derivatives on malaria transmissibility.

BACKGROUND: On the western border of Thailand the efficacy of mefloquine in the treatment of falciparum malaria has declined while gametocyte carriage rates have increased, which suggests increased transmissibility of these resistant infections. We compared the following antimalarial drugs in relation to subsequent Plasmodium falciparum gametocyte carriage: mefloquine, halofantrine, quinine, and the artemisinin derivatives. METHODS: Between 1990 and 1995 we assessed gametocytaemia in a series of prospective studies of antimalarial drug treatment in 5193 adults and children with acute uncomplicated falciparum malaria in an area of malarious hill forest on the western border of Thailand. Weekly parasite counts from thick and thin blood films were done during the 4-week (1990-93) or 9-week (1993-95) follow-up period. Gametocyte positivity rates and person gametocyte week (PGW) rates were calculated to measure gametocyte carriage and transmission potential. FINDINGS: In primary P falciparum infections the gametocyte carriage rate was significantly higher after treatment with mefloquine than after treatment with the artemisinin derivatives (PGW 34.1 [95% CI 25.2-42.9] vs 3.9 [1.9-5.9] per 1000 person weeks; relative risk 8.0 [4.1-15.6]; p<0.0001). Recrudescent infections were associated with increased gametocyte carrier rates (relative risk 2.2 [1.6-3.0]; p<0.0001), but retreatment with artemisinin derivatives reduced subsequent gametocyte carriage 18.5 fold [3.5-98] compared with mefloquine retreatment and 6.8 fold (3.1-15.1) compared with quinine retreatment (p<0.001). The introduction of the artemisinin derivatives in routine treatment at this study site in mid 1994 was associated with a reduction in the subsequent incidence of falciparum malaria of 47 (25-69)% INTERPRETATION: Although environmental changes affect vector numbers, and hence malaria incidence, artemisinin derivatives were found to reduce the transmission potential of falciparum malaria. Widespread introduction of artemisinin derivatives in the treatment of falciparum malaria may prevent the spread of multidrug resistance.

Adolescent↗

PubMed2004

Memantine hydrochloride: pharmacological and clinical profile.

Memantine (Axura, Merz Pharmaceuticals GmbH; Ebixa, H. Lundbeck A/S, Namenda, Forest Laboratories, Inc.) is an uncompetitive N-methyl-D-aspartate (NMDA) receptor antagonist with low to moderate affinity for the (+)MK-801 binding site. It is characterized as a voltage-sensitive open-channel NMDA receptor blocker that antagonizes NMDA receptor-mediated inward currents in vitro with an IC50 of 1-3 microM. In animal models, memantine displays both neuroprotective (antiexcitotoxic) and cognition-enhancing properties at therapeutically relevant concentrations. The strong voltage dependency and rapid blocking/unblocking kinetics of memantine are thought to be the basis for its excellent clinical tolerability. Recently completed clinical studies demonstrate positive effects of memantine in Alzheimer's disease both as a monotherapy and in patients receiving continuous donepezil treatment. Memantine treatment also has demonstrated significant improvement of cognitive performance in patients suffering from vascular dementia. Furthermore, the safety and tolerability of memantine in clinical trials has been excellent, with the incidence of premature withdrawals due to adverse events no greater than placebo and overall low frequencies of total adverse events. In 2002, memantine was approved by the European Medicines Agency (EMEA) for the treatment of moderately severe to severe Alzheimer's disease. More recently, memantine was approved in the US for the treatment of moderate to severe Alzheimer's disease (October 2003). Here, we review the most recent pharmacological and clinical data in dementia patients that has emerged from the systematic evaluation of memantine.

Alzheimer Disease↗

PubMed2001

Subjective effects and tolerability of the South American psychoactive beverage Ayahuasca in healthy volunteers.

RATIONALE: Ayahuasca is a South American psychoactive beverage that contains the naturally occurring psychedelic agent N,N-dimethyltryptamine (DMT). This "tea" has been used for centuries in religious and medicinal contexts in the rain forest areas of South America and is presently gaining the attention of psychedelic users in North America and Europe. OBJECTIVES: In the present study, the psychological effects and tolerability of ayvahuasca were assessed. METHODS: Three increasing doses of encapsulated freeze-dried ayahuasca (0.5, 0.75, and 1.0 mg DMT/kg body weight) were administered to six healthy male volunteers with prior experience in the use of this tea, in a single-blind crossover placebo-controlled clinical trial. RESULTS: Ayahuasca produced significant dose-dependent increases in five of the six subscales of the Hallucinogen Rating Scale, in the LSD, MBG, and A scales of the Addiction Research Center Inventory, and in the "liking", "good effects" and "high" visual analogue scales. Psychological effects were first noted after 30-60 min, peaked between 60-120 min, and were resolved by 240 min. The tea was well tolerated from a cardiovascular point of view, with a trend toward increase for systolic blood pressure. Modified physical sensations and nausea were the most frequently reported somatic-dysphoric effects. The overall experience was regarded as pleasant and satisfactory by five of the six volunteers, while one volunteer experienced an intensely dysphoric reaction with transient disorientation and anxiety at the medium dose and voluntarily withdrew from the study. CONCLUSIONS: Ayahuasca can be described as inducing changes in the perceptual, affective, cognitive, and somatic spheres, with a combination of stimulatory and visual psychoactive effects of longer duration and milder intensity than those previously reported for intravenously administered DMT.

Adult↗

PubMed2004

Sensitivity analyses of woody species exposed to air pollution based on ecophysiological measurements.

GOAL, SCOPE AND BACKGROUND: Air pollution has been of a major problem in the Pearl River Delta of south China, particularly during the last two decades. Emissions of air pollutants from industries have already led to damages in natural communities and environments in a wide range of the Delta area. Leaf parameters such as chlorophyll fluorescence, leaf area (LA), dry weight (DW) and leaf mass per area (LMA) had once been used as specific indexes of environmental stress. This study aims to determine in situ if the daily variation of chlorophyll fluorescence and other ecophysiological parameters in five seedlings of three woody species, Ilex rotunda, Ficus microcarpa and Machilus chinensis, could be used alone or in combination with other measurements for sensitivity indexes to make diagnoses under air pollution stress and, hence, to choose the correct tree species for urban afforestation in the Delta area. METHODS: Five seedlings of each species were transplanted in pot containers after their acclimation under shadowing conditions. Chlorophyll fluorescence measurements were made in situ by a portable fluorometer (OS-30, Opti-sciences, U.S.A). Ten random samples of leaves were picked from each species for LA measurements by area-meter (CI-203, CID, Inc., U.S.A). DW was determined after the leaf samples were dried to a constant weight at 65 degrees C. LMA was calculated as the ratio of DW/LA. Leaf N content was analyzed according to the Kjeldhal method, and the extraction of pigments was carried out according Lin et al. RESULTS AND DISCUSSION: The daily mean Fv/Fm (Fv is the variable fluorescence and Fm is the maximum fluorescence) analysis showed that Ilex rotunda and Ficus microcarpa were more highly resistant to pollution stress, followed by Machilus chinensis, implying that the efficiency of photosystem II in I. rotunda was less affected by air pollutants than the other two species. Little difference in daily change of Fv/Fm in I. rotunda between the polluted and the clean site was also observed. However, a relatively large variation of Fv/Fm appeared in the other two species, particularly in M. chinensis, suggesting that they were more sensitive to air pollutants than I. rotunda. The mean LA was reduced for all species growing at the polluted site. The mean LMA for all species exceeded the sclerophylly threshold given by Cowling and Campbell and increased for those under pollution stress, which could be explained as one of the acclimation strategies for plants to air pollution stress. Little difference in leaf chlorophyll content was observed in F. microcarpa and M. chinensis, while remarkable differences were found in I. rotunda growing at the polluted and the clean site. Content of leaf carotenoids was largely reduced in I. rotunda growing at the polluted site, but increased in F. microcarpa and M. chinensis, compared with plants growing at the clean site. Plants growing at the clean site had a lower leaf N content than those growing at the polluted site. In addition, species with a higher resistance to pollution stress showed less difference in leaf N content than those sensitive species. CONCLUSION: Based on Fv/Fm measurements of the three woody species, I. rotunda showed the highest resistance to air pollutants from ceramic industries, followed by F. microcarpa. M. chinensis was the most sensitive species to air pollution, had lowest capacities to cope with the air pollution stress, which was consistent with visual injury symptoms observed in the crown profiles of plants at the polluted site. Fv/Fm, LAM, LA, leaf pigments and N content could be used alone or in combination to diagnose the extent of the physiological injury. The ratio of Fv/Fm, however, was the best and most effective parameter. RECOMMENDATION AND OUTLOOK: Tree species which have higher air-pollutant resistance, as diagnosed by such ecophysiological parameters, should be considered first and planted widely for urban afforestation or forest regeneration in areas where the forest was seriously degraded or forest health was markedly effected by the same kind of air pollutants.

Air Pollutants↗

PubMed2006

Differences in whole-body protein turnover between Iberian and Landrace pigs fed adequate or lysine-deficient diets.

The capacity for protein deposition in Iberian pigs is lower than in modern (e.g., Landrace) pig breeds, and the reasons for this remain unknown. The hypothesis tested in this work is that under similar nutritional and physiological conditions, whole-body protein turnover as well as the protein synthesis to protein deposition ratio differs between Iberian and Landrace breeds, resulting in dissimilar protein deposition rates. As a main objective, these variables were compared at different protein and Lys intakes in growing gilts. The study examined the effect of Lys deficiency because this is the prevalent condition during the fattening period of the Iberian pig in the Mediterranean forest, where the main feed source is oak acorn, which provides approximately one-third of the available Lys present in an ideal protein. Three diets were tested within each breed: 2 diets with an optimal essential AA pattern, containing 12 or 16% CP as-fed, or a Lys-deficient diet (35% of the recommended Lys content). This diet was supplied at 12% CP for the Iberian and 16% CP for the Landrace pigs, respectively. The contrasts made were breed x dietary protein concentration and breed x AA pattern (adequate vs. inadequate Lys content). Cumulative urinary (15)N excretion over 60 h after receiving an oral dose of [(15)N]-glycine was used to calculate N flux. Mean BW for Landrace and Iberian pigs were 25.8 +/- 0.55 kg and 30.8 +/- 0.74 kg, respectively. Protein deposition (g of N/(kg(0.75).d) was lower in the Iberian than in the Landrace gilts (4 to 16%; P = 0.002) and increased with dietary protein content. In contrast, protein synthesis and degradation [g of N/(kg(0.75).d)] were greater for the Landrace breed (16 to 18 and 23%, respectively, for the 2 dietary protein contents studied; P < 0.05), but no breed differences were detected in fractional protein synthesis and degradation rates. The ratio of protein synthesis:protein deposition (S/PD) did not change with dietary protein concentration or breed and achieved a mean value of 5.4. Irrespective of breed, Lys deficiency had a strong negative effect on N balance (P < 0.001) and increased the ratio of S/PD (P = 0.012). The greater rates of protein deposition, synthesis, and degradation in Landrace pigs than in Iberian pigs fed optimal AA-pattern diets were then attributed to differences in body protein mass. Consequently, these results validate the hypothesis of unequal synthesis and degradation, but not of unequal S/PD, between breeds.

Animal Feed↗

PubMed2001

Safety and pharmacokinetics of single doses of (+)-calanolide a, a novel, naturally occurring nonnucleoside reverse transcriptase inhibitor, in healthy, human immunodeficiency virus-negative human subjects.

(+)-Calanolide A is a novel, naturally occurring, nonnucleoside inhibitor of human immunodeficiency virus type 1 (HIV-1) reverse transcriptase first isolated from a tropical tree (Calophyllum lanigerum) in the Malaysian rain forest. Previous studies have demonstrated that (+)-calanolide A has specific activity against the reverse transcriptase of HIV-1 and a favorable safety profile in animals. In addition, (+)-calanolide A exhibits a unique HIV-1 resistance profile in vitro. The safety and pharmacokinetics of (+)-calanolide A was examined in four successive single-dose cohorts (200, 400, 600, and 800 mg) in healthy, HIV-negative volunteers. In this initial phase I study, the toxicity of (+)-calanolide A was minimal in the 47 subjects treated. Dizziness, taste perversion, headache, eructation, and nausea were the most frequently reported adverse events. These events were not all judged to be related to study medication nor were they dose related. While 51% of subjects reported mild and transient dizziness, in many cases this appeared to be temporally related to phlebotomy. Calculation of the terminal-phase half-life (t(1/2)) was precluded by intrasubject variability in the 200-, 400-, and 600-mg dose cohorts but was approximately 20 h for the 800-mg dose group. (+)-Calanolide A was rapidly absorbed following administration, with time to maximum concentration of drug in plasma (T(max)) values occurring between 2.4 and 5.2 h postdosing depending on the dose. Plasma levels of (+)-calanolide A at all dosing levels were quite variable; however, both the mean concentration in plasma (C(max)), and the area under the plasma concentration-time curve increased proportionately in relation to the dose. Although raw plasma drug levels were higher in women than in men, when doses were normalized for body mass, the pharmacokinetic profiles were virtually identical with those observed for males. In general, levels of (+)-calanolide A in human plasma were higher than would have been predicted from animal studies, yet the safety profile remained benign. In conclusion, this study demonstrated the safety and favorable pharmacokinetic profile of single doses of (+)-calanolide A in healthy, HIV-negative individuals.

Adolescent↗

PubMed2001

Deposition and pharmacokinetics of flunisolide delivered from pressurized inhalers containing non-CFC and CFC propellants.

Our objective was to assess the deposition and pharmacokinetics of a novel formulation of flunisolide (Aerobid, Forest Laboratories) in hydrofluoroalkane (HFA) 134a delivered by pressurized metered dose inhaler (pMDI). The design was a two-way crossover investigation in 12 healthy male subjects comparing HFA-134a flunisolide by pMDI versus pMDI plus 50 mL spacer device. Four of these subjects also took part in a two-way crossover investigation comparing chlorofluorocarbon (CFC) flunisolide pMDI versus pMDI plus Aerochamber holding chamber. The imaging technique of gamma scintigraphy was used to quantify total and regional lung deposition of flunisolide. Plasma levels of flunisolide and its major metabolite (6beta-OH flunisolide) were also determined. The spacer and Aerochamber reduced oropharyngeal deposition dramatically for both the HFA and CFC products (mean 59.8 to 14.9% (p < 0.01) of ex-valve (metered) dose for HFA product; 66.3 to 12.3% (p < 0.01) of ex-valve dose for CFC product) owing to deposition of part of the dose on the walls of the add-on devices themselves. Lung deposition averaged 22.6 and 40.4% (p < 0.01) of the ex-valve dose for the HFA formulation used with pMDI alone and with pMDI plus spacer. Mean lung deposition of the CFC formulation delivered via the Aerochamber (mean 23.4%) was higher than that for the CFC pMDI alone (mean 17.0%), but this difference was not statistically significant. Lung deposition expressed as percentage ex-device (delivered) dose averaged 68.3% for HFA pMDI plus spacer and 19.7% for CFC pMDI. Plasma levels of flunisolide were higher for the pMDI plus spacer than for pMDI alone, reflecting higher lung deposition via the spacer, but plasma levels of the 6beta-OH flunisolide metabolite were higher for the pMDI alone as a consequence of higher oropharyngeal deposition. When delivered via the spacer, pulmonary targeting of the flunisolide HFA formulation was improved compared with the CFC formulation, which should benefit patients by providing satisfactory asthma therapy from a much-reduced delivered dose of flunisolide.

Administration, Inhalation↗

PubMed2004

A rapid and systematic review and economic evaluation of the clinical and cost-effectiveness of newer drugs for treatment of mania associated with bipolar affective disorder.

OBJECTIVES: To evaluate the clinical and cost-effectiveness of quetiapine, olanzapine and valproate semisodium in the treatment of mania associated with bipolar disorder. DATA SOURCES: Electronic databases; industry submissions made to the National Institute for Clinical Excellence. REVIEW METHODS: Randomised trials and economic evaluations that evaluated the effectiveness of quetiapine, olanzapine or valproate semisodium in the treatment of mania associated with bipolar disorder were selected for inclusion. Data were extracted by one reviewer into a Microsoft Access database and checked for quality and accuracy by a second. The quality of the cost-effectiveness studies was assessed using a checklist updated from that developed by Drummond and colleagues. Relative risk and mean difference data were presented as Forest plots but only pooled where this made sense clinically and statistically. Studies were grouped by drug and, within each drug, by comparator used. Chi-squared tests of heterogeneity were performed for the outcomes if pooling was indicated. A probabilistic model was developed to estimate costs from the perspective of the NHS, and health outcomes in terms of response rate, based on an improvement of at least 50% in a patient's baseline manic symptoms derived from an interview-based mania assessment scale. The model evaluated the cost-effectiveness of the alternative drugs when used as part of treatment for the acute manic episode only. RESULTS: Eighteen randomised trials met the inclusion criteria. Aspects of three of the quetiapine studies were commercial-in-confidence. The quality of the included trials was limited and overall, key methodological criteria were not met in most trials. Quetiapine, olanzapine and valproate semisodium appear superior to placebo in reducing manic symptoms, but may cause side-effects. There appears to be little difference between these treatments and lithium in terms of effectiveness, but quetiapine is associated with somnolence and weight gain, whereas lithium is associated with tremor. Olanzapine as adjunct therapy to mood stabilisers may be more effective than placebo in reducing mania and improving global health, but it is associated with more dry mouth, somnolence, weight gain, increased appetite, tremor and speech disorder. There was little difference between these treatments and haloperidol in reducing mania, but haloperidol was associated with more extrapyramidal side-effects and negative implications for health-related quality of life. Intramuscular olanzapine and lorazepam were equally effective and safe in one very short (24 hour) trial. Valproate semisodium and carbamazepine were equally effective and safe in one small trial in children. Olanzapine may be more effective than valproate semisodium in reducing mania, but was associated with more dry mouth, increased appetite, oedema, somnolence, speech disorder, Parkinson-like symptoms and weight gain. Valproate semisodium was associated with more nausea than olanzapine. The results from the base-case analysis demonstrate that choice of optimal strategy is dependent on the maximum that the health service is prepared to pay per additional responder. For a figure of less than 7179 British pounds per additional responder, haloperidol is the optimal decision; for a spend in excess of this, it would be olanzapine. Under the most favourable scenario in relation to the costs of responders and non-responders beyond the 3-week period considered in the base-case analysis, the incremental cost-effectiveness ratio of olanzapine is reduced to 1236 British pounds. CONCLUSIONS: In comparison with placebo, quetiapine, olanzapine and valproate semisodium appear superior in reducing manic symptoms, but all drugs are associated with adverse events. In comparison with lithium, no significant differences were found between the three drugs in terms of effectiveness, and all were associated with adverse events. Several limitations of the cost-effectiveness analysis exist, which inevitably means that the results should be treated with some caution. There remains a need for well-conducted, randomised, double-blind head-to-head comparisons of drugs used in the treatment of mania associated with bipolar disorder and their cost-effectiveness. Participant demographic, diagnostic characteristics, the treatment of mania in children, the use of adjunctive therapy and long-term safety issues in the elderly population, and acute and long-term treatment are also subjects for further study.

Antimanic Agents↗

PubMed2001

A rapid and systematic review of the clinical effectiveness and cost-effectiveness of topotecan for ovarian cancer.

BACKGROUND: Ovarian cancer is the most common gynaecological cancer with an annual incidence of 21.6 per 100,000 in England and Wales. Due to the often asymptomatic nature of the early stages of the disease, most cases are not detected until the advanced stages. Consequently, the prognosis after diagnosis is poor and the 5-year survival rate in the UK is only about 30%. Current recommendations suggest that first-line chemotherapy for ovarian cancer should involve paclitaxel and platinum (Pt)-based therapy (cisplatin/ carboplatin), however, most patients develop resistant or refractory disease and require second-line therapy. Patients may respond to re-challenge with Pt-agents if the treatment-free interval is > 6 months, but an alternative is often required. Topotecan is one of six drugs currently licensed in the UK for second-line therapy, and recent reviews suggest that it has modest efficacy in the treatment of advanced disease and performs favourably against paclitaxel. However, these reviews are based on a limited number of reports mainly consisting of non-randomised Phase I and II studies. OBJECTIVES OF THE REVIEW: To examine the clinical effectiveness and cost-effectiveness of oral and intravenous topotecan (Hycamtin, SmithKline Beecham, UK) for the treatment of all stages of ovarian cancer. METHODS SEARCH STRATEGY: Sixteen electronic databases from inception to September 2000 and Internet resources were searched, in addition to the bibliographies of retrieved articles and submissions from pharmaceutical companies. METHODS INCLUSION AND EXCLUSION CRITERIA: Two reviewers independently screened all titles/abstracts and included/excluded studies based on full copies of manuscripts. Any disagreements were resolved through discussion. Only randomised controlled trials (RCTs) and full economic evaluations comparing topotecan to non-topotecan regimens were included. All stages of therapy and disease were considered, and the outcomes included were survival, response, symptom relief, quality of life, adverse effects and costs. METHODS: DATA EXTRACTION STRATEGY: Data were extracted into an Access database by one reviewer and checked by a second. Any disagreements were resolved through discussion. METHODS: QUALITY ASSESSMENT STRATEGY: Two reviewers, using specified criteria, independently assessed the quality of the clinical effectiveness studies and the economic evaluations. Any disagreements were resolved through discussion. METHODS: ANALYSIS STRATEGY: Due to the limited number of studies included in the review and the fact that they compared topotecan with different comparators, the out-come data could not be pooled statistically. Clinical effectiveness data are discussed separately under the different outcome subheadings. For time-to-event data, hazard ratios with 95% confidence intervals are presented where available, and for the remaining outcomes, relative risks are reported or calculated where sufficient data were available. Relative risk data are also presented in the form of Forest plots without pooled estimates. Economic data are presented in the form of a summary and critique of the evidence, and a grading (A-I) assigned to each study indicating the direction and magnitude of the cost-effectiveness data. RESULTS INCLUDED STUDIES: A total of 568 titles/abstracts were identified and screened for relevance. Full copies of 72 papers were assessed and seven published manuscripts reporting details of two studies of clinical effectiveness and one economic evaluation were included. Further details of the two clinical effectiveness studies and two new economic evaluations were identified from confidential company submissions. Overall, two international multicentre RCTs of effectiveness comparing topotecan with paclitaxel (trial 039) and topotecan with caelyx (trial 30-49) were included in the review. The three economic evaluations included in the review comprised one cost-minimisation analysis (CMA) comparing topotecan with caelyx, one cost-consequences analysis (CCA) comparing topotecan with paclitaxel, etoposide and altretamine and one cost-effectiveness analysis (CEA) comparing topotecan with paclitaxel. RESULTS: QUALITY OF CLINICAL EFFECTIVENESS DATA: Both clinical effectiveness studies (trial 30-49 and 039) were of reasonable quality, although it was unclear whether either performed valid intention-to-treat analyses. In addition, trial 30-49 failed to state whether the outcome assessors were blinded to treatment allocation. RESULTS --QUALITY OF ECONOMIC EVALUATIONS: The CCA (comparing topotecan with three comparators) was of poor quality and of little relevance to the UK NHS. The CMA and CEA were of reasonable quality overall and relevant to the UK NHS. However, both, in particular the CEA, suffered from methodological problems, and thus their findings should be interpreted with caution. RESULTS: ASSESSMENT OF CLINICAL EFFECTIVENESS: The assessment of clinical effectiveness was based on limited data. Only two trials with a total of 709 participants were identified. In general, with a few minor exceptions, there were no statistically significant differences between topotecan and paclitaxel, or topotecan and caelyx in survival, response rate, median time to response, median duration of response and quality of life. Significant differences that were reported were mainly identified in subgroup analyses (Pt-sensitive disease and disease without ascites) of questionable validity and their relevance to a general advanced ovarian cancer patient population undergoing second-line chemotherapy is unclear. However, statistically significant differences were observed in the incidence of adverse effects. Topotecan was associated with increased incidences of haematological toxicities (including neutropenia, leukopenia, anaemia and thrombocytopenia), alopecia, nausea and vomiting. Caelyx-treated patients suffered from significantly increased incidences of Palmar-Plantar erythrodysesthesia, stomatitis, mucous membrane disorders and skin rashes. Paclitaxel was associated with significant increases in alopecia, arthralgia, myalgia, neuropathy, paraesthesiae, skeletal pain and flushing. RESULTS: ASSESSMENT OF COST-EFFECTIVENESS: The assessment of cost-effectiveness was also based on limited data, with three evaluations identified, one of which was not relevant. The two remaining studies, comparing topotecan with paclitaxel (CEA) and topotecan with caelyx (CMA), both used effectiveness data from multicentre RCTs and based their costs on 1999/2000 UK sources. The evaluations were conducted from a UK NHS perspective and findings presented in GB pounds/Euros. Topotecan for the second-line treatment of advanced ovarian cancer was shown to be more cost-effective than paclitaxel (32,513 GB pounds versus 46,186 GB pounds per person in terms of any response (complete or partial), incremental cost-effectiveness = 3065 GB pounds) in all respects except cost per time without toxicity or symptoms, but less cost-effective than caelyx (14,023 GB pounds versus 9979 GB pounds per person regardless of whether the patient responded). However, direct comparisons of the cost findings between the two studies is difficult because they used different designs, different time horizons for the cost analyses and the findings were presented as costs per person for only patients who responded in one study (topotecan versus paclitaxel) and costs per person regardless of whether they responded in the other study (topotecan versus caelyx). CONCLUSIONS: This review indicates that there is little evidence in the form of RCTs on which to base an assessment of the effectiveness of topotecan as second-line therapy for advanced ovarian cancer. The evidence suggests there were no statistically significant differences overall between topotecan and paclitaxel, or topotecan and caelyx in clinical outcomes. However, statistically significant differences were observed in the incidence of adverse effects. The clinical significance of the findings is not discussed. Overall, the effects of topotecan could at best be described as modest, but the alternative agents offer no real advantages except fewer side-effects and possibly improved cost-effectiveness. Both of the clinical effectiveness studies on which this evidence is based had methodological flaws, the most serious being the lack of a blinded assessor in the topotecan versus caelyx trial, which is important for unbiased assessment of response outcomes. The economic evaluations also suffered from a number of potential problems. CONCLUSIONS: RECOMMENDATIONS FOR RESEARCH: Further good quality RCTs and CEAs are required comparing topotecan with other licensed and potentially useful (soon to be licensed) second-line treatments for ovarian cancer. At present, it is difficult to make any decisions about topotecan and other drugs for second-line therapy without good quality direct comparisons. In view of the ongoing studies identified, an update of the current review should be considered in approximately 18 months (Summer 2002) or possibly sooner if the recently commissioned National Institute for Clinical Excellence review of caelyx for ovarian cancer identifies additional data relevant to topotecan.

Antineoplastic Agents↗