Prescrire international
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Prescrire international · Jun 2005
Comparative StudyAdjuvant hormone therapy for breast cancer: alternatives to tamoxifen.
(1) After surgical excision of hormone-receptor-positive non metastatic breast cancer in postmenopausal women, a meta-analysis of 55 trials has shown that adjuvant tamoxifen, 20 mg/day for 5 years, reduces the risk of relapse by 8% and the risk of death by 5% (absolute values). The benefit of treatment beyond 5 years remains to be established. (2) Preliminary four-year results from a double-blind randomised controlled trial comparing anastrozole with tamoxifen (ATAC trial) indicated an advantage for anastrozole in reducing the risk of relapse. There was no difference in survival rate. ⋯ The trial's methodology is controversial, however, and conclusions concerning the relative risk-benefit balances of these two drugs must await the full 5-year results. (3) A double-blind placebo-controlled trial of letrozole, prescribed after 5 years of adjuvant tamoxifen, was stopped early after a median follow-up of 2.4 years. When extrapolated to 4 years, the results suggest that letrozole reduced the risk of relapse (7%, compared to 13% with tamoxifen) but had no effect on survival. (4) A double-blind trial comparing tamoxifen with exemestane in 4742 women who had already received tamoxifen for two to three years showed a higher three-year disease-free survival rate with exemestane (91.5% versus 86.8%). Overall survival did not differ between the two groups. (5) Pending results of further clinical trials, tamoxifen remains the first-line adjuvant hormone therapy for most postmenopausal women with hormone-receptor-positive non metastatic breast cancer.
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Prescrire international · Jun 2005
Comparative StudyChickenpox vaccines: new drugs. A favourable risk-benefit balance in some situations.
(1) Chickenpox is generally mild. Most severe cases of chickenpox occur in immunocompromised patients, adults, and pregnant women (and their foetuses). (2) Two live attenuated chickenpox vaccines derived from the same strain of varicella virus (Oka) are marketed in France, under the trade names Varilrix and Varivax. (3) They have not been adequately evaluated in immunocompromised children. (4) The impact of routine vaccination of women of child-bearing age on complications of chickenpox during pregnancy has not been studied. (5) Immunogenicity studies in several thousand immunocompetent children aged from 1 to 12 years show that the vaccine is almost always immunogenic after a single injection. Other comparative studies in adolescents and adults show that two injections are needed, at least two months apart. (6) A double-blind placebo-controlled trial including 513 immunocompetent children showed that Varilrix prevented 88% of cases of chickenpox after a median follow-up of 29 months, but no data on severe chickenpox were reported. ⋯ There seems to be no increase in the risk of herpes zoster in vaccinated children nor is there any firm evidence that chickenpox vaccination increases the incidence of herpes zoster in the general population. (11) Little information is available on vaccination during pregnancy. As a precaution, however, pregnant women should not be vaccinated. (12) Mass vaccination does not appear to be justified: chickenpox is generally mild during childhood, and several questions concerning the effects of the vaccine remain unanswered. (13) Chickenpox vaccination should be restricted to specific groups of non immune immunocompetent adults who are in a position to transmit chickenpox to immunodeficient contacts (e.g. health care personnel and kindergarten staff); adults who have been in contact with a case of chickenpox within the past three days; and children awaiting transplantation. The potential benefits and risks of vaccinating immunocompromised patients should be assessed on a case by case basis.
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Prescrire international · Jun 2005
Tramadol oral solution: new drug. Poorly evaluated and potentially dangerous in children.
(1) Codeine, either used alone or in combination with paracetamol, is the standard step-2 opiate analgesic for children from the age of one year. (2) An oral solution of tramadol, another step-2 opiate analgesic, was recently approved in France for the treatment of children at least three years of age. (3) The only clinical trials of tramadol in this age group focused on short-term treatment of postoperative pain. Tramadol has not been compared with codeine, ibuprofen, or correctly dosed paracetamol (step-1 analgesic). Tramadol has been compared with diclofenac, a nonsteroidal antiinflammatory drug, in a trial that included patients over 11 years of age (including adults), but the results of this trial are uninformative because patients were not blinded and no separate paediatric subgroup analysis was carried out. (4) The adverse effects of tramadol in children appear to be mild but frequent (especially vomiting). (5) As with codeine, deaths have been reported following accidental overdose with oral tramadol in children. (6) There is no justification for prescribing such a potentially harmful drug with poorly documented efficacy.