Topotecan. A review of its potential in advanced ovarian cancer.

The topoisomerase I inhibitor topotecan has shown antitumour activity against a variety of tumour types in vitro and in vivo. Topotecan in combination with drugs that induce DNA damage generally results in synergistic killing of tumour cells in vitro. As the activity of topotecan is related to exposure time, the drug is administered by intravenous infusion either continuously or once daily over a 30-minute period for several consecutive days. A 30-minute infusion of topotecan 1.5 mg/m2 on 5 consecutive days every 3 weeks produced response rates of up to approximately 20% in patients with advanced ovarian cancer who had failed to respond to platinum-based regimens or relapsed after initial response to such regimens. No significant differences in efficacy were apparent between topotecan and paclitaxel in a phase III study in patients with recurrent ovarian cancer, although a trend in favour of topotecan was evident for all major efficacy parameters. Non-cumulative myelosuppression, including neutropenia, thrombocytopenia and anaemia, is the dose-limiting toxicity associated with topotecan. Myelo-suppression was significantly more common with topotecan than with paclitaxel in a single comparative study. Non-haematological adverse events in topotecan recipients are generally mild and include alopecia, nausea, vomiting, and other gastrointestinal problems. Thus, topotecan has modest efficacy in the treatment of recurrent advanced ovarian cancer, with clinical activity similar to that of paclitaxel in a large randomised phase III study in this setting. Combinations of paclitaxel and a platinum compound are being used increasingly for first-line therapy, although relapse rates remain significant. Topotecan is therefore a suitable second-line option, providing antitumour response for some patients whose disease has relapsed after, or is refractory to, platinum-based therapy. Its wider potential when used either alone or in combination regimens should become clearer from ongoing studies.

Amphotericin-B colloidal dispersion. A review of its use against systemic fungal infections and visceral leishmaniasis.

UNLABELLED: Formulation of amphotericin B with sodium cholesteryl sulphate alters the pharmacokinetic properties of the drug, particularly reducing its distribution to the kidneys. The antifungal activity in vitro of amphotericin B colloidal dispersion (ABCD) is similar to that of conventional amphotericin B (C-AmB) against true pathogenic organisms including Blastomyces, Coccidioides, Histoplasma and Paracoccidioides species and the opportunistic organisms such as Candida and Cryptococcus species. In animal models, ABCD was generally less effective than an identical dose of C-AmB, but overall was more effective because of its improved therapeutic index. Although ABCD appeared to be more effective than C-AmB in resolving infection and improving survival in patients with proven or probable invasive aspergillosis, the retrospective design of the study and the greater prevalence of neutropenia in patients treated with the conventional formulation necessitate cautious interpretation of the results. ABCD has been effective and seldom caused nephrotoxicity in patients with fungal infection who had previously failed to adequately respond or had developed renal toxicity with C-AmB. Similarly, ABCD was effective in patients with proven or suspected fungal infection after bone marrow transplantation. Preliminary results from a pilot study comparing ABCD and C-AmB in patients with neutropenia and persistent fever reported similar response rates with both formulations. ABCD is an effective treatment for visceral leishmaniasis in immunocompetent patients. In 1 study, about 12% of ABCD recipients discontinued the drug because of adverse events; infusion-related events were the most common cause of discontinuation. The renal tolerability of ABCD is better than that of C-AmB. ABCD appears to be an effective alternative to conventional amphotericin B in patients with invasive aspergillosis or visceral leishmaniasis and in those with proven or suspected systemic fungal infection who are intolerant of the conventional formulation or have pre-existing renal impairment. Preliminary data also suggest that ABCD is an alternative to C-AmB when used empirically in patients with neutropenia and fever. Nevertheless, the efficacy of ABCD compared with that of the conventional formulation has yet to be adequately demonstrated and the role of ABCD relative to that of liposomal and other lipid-based formulations has not been determined. CONCLUSIONS: ABCD, like other lipid-based and liposomal formulations of amphotericin B, has been designed to deliver the active drug to the target site, while reducing renal toxicity. The aim of increasing the therapeutic index compared with C-AmB has been achieved.

Moexipril. A review of its use in the management of essential hypertension.

UNLABELLED: Moexipril is a prodrug which is hydrolysed after oral administration to its active metabolite moexiprilat, an inhibitor of the angiotensin converting enzyme (ACE). Once daily administration of moexipril 7.5 or 15 mg effectively reduces blood pressure in patients with essential hypertension (including the elderly and postmenopausal women with this condition). In double-blind randomised comparative studies, moexipril 7.5 to 15 mg once daily showed similar efficacy to other antihypertensive agents, including captopril, hydrochlorothiazide, atenolol, metoprolol, sustained release verapamil and nitrendipine. Combined therapy with hydrochlorothiazide and moexipril had a significantly greater antihypertensive effect than either agent alone. Moexipril is well tolerated by the majority of patients and compares well in this respect with other antihypertensive agents. Its tolerability profile appears to be characteristic of ACE inhibitors as a class (the most common adverse events being headache, symptoms of upper respiratory tract infection and cough). Moexipril generally had no clinically significant effect on lipid, glucose or electrolyte metabolism or haematological parameters, and, in particular, it was not associated with any significant changes in lipid or glucose metabolism in postmenopausal women (with or without hormone replacement therapy). CONCLUSIONS: Once daily moexipril is a useful agent for the treatment of essential hypertension, which compares well with currently available options in terms of clinical efficacy and tolerability. In addition, clinical experience to date supports its use in postmenopausal women.

Tazarotene.

Tazarotene is a topical retinoid that appears to exert its effects via retinoic acid receptors. It normalises differentiation and proliferation of keratinocytes and has an anti-inflammatory effect. Topical tazarotene 0.05% or 0.1% gel was effective in the treatment of plaque psoriasis in clinical trials and its therapeutic effect was maintained for at least 12 weeks after treatment discontinuation in some patients. In one study in patients with psoriasis, tazarotene had similar efficacy to fluocinonide in reducing plaque elevation, but not erythema. In another study, tazarotene was reported to be less effective than fluocinonide. Combination treatment with tazarotene plus a mid- or high-potency corticosteroid was more effective in the treatment of psoriasis than tazarotene alone. Topical tazarotene 0.1% gel significantly reduced lesion counts in patients with mild to moderate facial acne vulgaris. Skin irritation is a common adverse event with topical tazarotene, but it is mainly of mild to moderate severity. Tazarotene is not recommended for use in women who are, or may become, pregnant.

Propionyl-L-carnitine.

Propionyl-L-carnitine stimulates energy production in ischaemic muscles by increasing citric acid cycle flux and stimulating pyruvate dehydrogenase activity. The free radical scavenging activity of the drug may also be beneficial. Propionyl-L-carnitine improves coagulative fibrinolytic homeostasis in vasal endothelium and positively affects blood viscosity. Improvements in maximum walking distance (MWD) correlated positively with increased mitochondrial oxidative adenosine triphosphate (ATP) synthesis in a study in patients with peripheral arterial disease. Oral propionyl-L-carnitine 1 to 3 g/day significantly improved mean MWD compared with placebo in patients with peripheral arterial obstructive disease (Fontaine Leriche stage II) in double-blind multicentre phase III studies (mean improvements ranged from 21 to 50% with placebo and from 33 to 73% with propionyl-L-carnitine). In one phase III study, propionyl-L-carnitine 1 to 3 g/day significantly improved mean MWD (measured by treadmill) compared with placebo (by 73 vs 46% after 24 weeks) in patients with intermittent claudication. Oral propionyl-L-carnitine therapy was associated with significant improvements in quality of life compared with placebo in patients with a baseline MWD < 250m. Propionyl-L-carnitine appears to be well tolerated, showing a similar incidence of adverse events to that reported in placebo recipients.

Liposomal amphotericin B. Therapeutic use in the management of fungal infections and visceral leishmaniasis.

Incorporation of amphotericin B into small unilamellar liposomes (AmBisome) alters the pharmacokinetic properties of the drug, but allows it to retain significant in vitro and in vivo activity against fungal species, including Candida, Aspergillus and Cryptococcus, and parasites of the genus Leishmania. Used as prophylaxis against fungal infections in immunocompromised patients, liposomal amphotericin B appeared to reduce the incidence of both fungal colonisation and proven fungal infections, but did not affect overall survival. Empirical therapy with liposomal amphotericin B in immunocompromised adults or children with suspected fungal infections was at least as effective as therapy with conventional amphotericin B. In the largest noncomparative studies, liposomal amphotericin B produced mycological eradication in 40 and 83% of patients with proven Candida infections and 41 and 60% with proven Aspergillus infections; however, these studies included relatively few patients. Mycological eradication rates of 67 to 85% in patients with cryptococcal meningitis have been reported. Liposomal amphotericin B is an effective treatment for visceral leishmaniasis in immunocompetent adults and children, including those with severe or drug-resistant disease. The drug also produces good response rates in immunocompromised patients; however, relapse rates in these patients are high. Liposomal amphotericin B is generally well tolerated. Few patients require discontinuation or dose reduction of the drug because of adverse events. The most frequently reported adverse events are hypokalaemia, nephrotoxicity and infusion-related reactions; however, these occur significantly less often after liposomal amphotericin B than after the conventional formulation of the drug. The acquisition cost of liposomal amphotericin B is higher than that of conventional amphotericin B. Cost-effectiveness analysis did not clearly show an economic benefit for empirical liposomal amphotericin B antifungal therapy in adults; however, one model suggested that initial empirical therapy with the liposomal formulation in children may cost less per cure than initial therapy with the conventional formulation. Liposomal amphotericin B appears to be an effective alternative to conventional amphotericin B in the management of immunocompromised patients with proven or suspected fungal infections. Use of the drug is facilitated by its greatly improved tolerability profile compared with conventional amphotericin B. Because of this, liposomal amphotericin should be preferred to conventional amphotericin B in the management of suspected or proven fungal infections in immunocompromised patients with pre-existing renal dysfunction, amphotericin B-induced toxicity or failure to respond to conventional amphotericin B. Liposomal amphotericin B may also be considered for first- or second-line treatment of immunocompetent patients with visceral leishmaniasis.

Formoterol. An update of its pharmacological properties and therapeutic efficacy in the management of asthma.

Formoterol, a selective beta 2-adrenoceptor agonist, produces effective dose-proportional bronchodilation, which persists for up to 12 hours, in patients with reversible obstructive respiratory disease. Bronchodilation is significant within minutes of inhalation, maximal within 2 hours, and at therapeutic doses is equivalent to that produced by standard doses of traditional beta 2-agonists. In single-dose studies comparing the two long-acting beta 2-agonists formoterol and salmeterol, significant bronchodilation is achieved more rapidly with formoterol than salmeterol. Duration of bronchodilation is similar with both drugs. The therapeutic efficacy of inhaled formoterol has been equal to or greater than that of salbutamol (albuterol), fenoterol and terbutaline in both short and long term clinical trials. Formoterol reduces symptoms of nocturnal asthma and reduces the need for rescue medication compared with salbutamol. Recent studies have shown that the addition of inhaled formoterol 12 or 24 micrograms twice daily to existing inhaled corticosteroid regimens improves lung function and reduces asthma symptoms compared with placebo. In one well designed study, the frequency of severe exacerbations of asthma over 12 months was decreased by adding formoterol to existing regimens of inhaled corticosteroids. Tolerance to the bronchodilator response of formoterol has not been observed in long term clinical trials. Because of its long duration of action, formoterol offers significant therapeutic advantages over shorter-acting beta 2-agonists in the treatment of nocturnal and exercise-induced asthma. Formoterol is effective in preventing exercise-induced asthma in adults and children and confers significantly more protection than salbutamol when administered 3 and 12 hours before exercise. In general, inhaled formoterol is well tolerated. The most commonly reported adverse effects, tremor and palpitations, are those traditionally associated with the use of beta 2-agonists. Oral formoterol and high doses of inhaled formoterol are associated with more adverse events than are the recommended doses of 6 to 24 micrograms. Formoterol is currently recommended for use as an alternative to increasing inhaled steroid dosage in patients whose symptoms are inadequately controlled despite therapy with low to moderate doses of inhaled steroids and intermittent short-acting beta 2-agonists, and results of recent studies support therapeutic guidelines. Long term clinical studies comparing formoterol and salmeterol have not yet been published. Further studies to evaluate the earlier use of formoterol in patients with mild to moderate asthma are needed to determine the role and long term safety of formoterol in the management of asthma.

Zafirlukast. A review of its pharmacology and therapeutic potential in the management of asthma.

Zafirlukast is a competitive and selective leukotriene receptor antagonist indicated for the prophylaxis and treatment of chronic asthma. The rationale for the development of leukotriene antagonists was based on in vitro and in vivo data demonstrating the extensive role of the cysteinyl leukotrienes C4 (LTC4), D4 (LTD4) and E4 (LTE4) in the pathogenesis of asthma. Initial data have demonstrated an improvement in pulmonary function and symptom control and a reduction in the use of short-acting inhaled beta 2-adrenoceptor agonist therapy in patients with mild to moderate asthma treated with oral zafirlukast at the recommended dosage of 20 mg twice daily. Available data also suggest that zafirlukast may significantly reduce the incidence of asthma exacerbations. Data on the comparative efficacy of zafirlukast and existing antiasthma medications are limited. Results from 2 double-blind randomised studies comparing zafirlukast 20 mg twice daily with sodium cromoglycate aerosol or dry powder inhalation reported similar efficacy for both drugs. In a comparison with inhaled beclomethasone dipropionate (0.2 to 0.25 mg twice daily), improvements in morning peak expiratory flow rate, forced expiratory volume in 1 second and daytime symptom score were significantly less with zafirlukast 20 mg twice daily for 6 weeks. However, available data suggest that patient compliance and patient preference may be greater with oral zafirlukast 20 mg twice daily than with twice-daily inhaled corticosteroid therapy. Confounding results from 2 studies preclude any clear conclusions regarding the potential steroid-sparing effect of zafirlukast at the recommended dosage of 20 mg twice daily. Furthermore, Churg-Strauss syndrome has been reported in 6 patients who were being withdrawn from oral corticosteroid therapy while receiving treatment with oral zafirlukast. It is, therefore, recommended that zafirlukast-treated patients who require a reduction in their oral corticosteroid therapy are closely monitored. Zafirlukast is generally well tolerated. Reports of elevated liver enzymes in patients receiving high dosages of zafirlukast (80 mg twice daily) preclude the use of dosages exceeding 40 mg twice daily. Careful monitoring is necessary in zafirlukast-treated patients receiving concomitant therapy with drugs such as warfarin, terfenadine and erythromycin because of the potential for drug interactions. Thus, zafirlukast is a potentially useful addition to current antiasthma therapies in patients with mild to moderate asthma. Because zafirlukast is administered orally, it may be particularly beneficial in patients poorly compliant with asthma therapy as a result of poor inhaler technique. Further investigation of the efficacy of zafirlukast is expected to more clearly define its position in the management of asthma.

Mibefradil. A review of its pharmacodynamic and pharmacokinetic properties, and therapeutic efficacy in the management of hypertension and angina pectoris.

Mibefradil belongs to a new class of calcium antagonists, the tetralol derivatives. It selectively blocks T-type calcium channels in contrast to other calcium antagonists which block only L-type channels. Mibefradil relaxes coronary arteries without suppressing myocardial contractility and causes a dose-related decrease in heart rate. When given orally once daily to patients with hypertension mibefradil produces a dose-related decrease in blood pressure which is sustained for 24 hours and improves exercise performance in patients with stable angina pectoris. In patients with generally mild to moderate hypertension oral mibefradil was superior to nifedipine SR and diltiazem CD, tended to be more effective than nifedipine GITS and had similar efficacy to amlodipine. Mibefradil 50 to 100mg once daily also has antianginal and anti-ischaemic effects. The drug improves the duration of symptom-limited exercise and the time to onset of ischaemia, and reduces the frequency of anginal attacks and consumption of nitroglycerin. Its efficacy is similar to that of diltiazem and tends to be greater than that of amlodipine in patients with stable angina. Mibefradil is generally well tolerated and is associated with a lower incidence of leg oedema than amlodipine and nifedipine. Thus, mibefradil is a calcium antagonist with a predictable cardiovascular profile, which, on the basis of available clinical data, is an effective alternative to other drugs widely used in the treatment of hypertension and stable angina pectoris.

Fenoldopam: a review of its pharmacodynamic and pharmacokinetic properties and intravenous clinical potential in the management of hypertensive urgencies and emergencies.

Fenoldopam is a dopamine agonist that causes peripheral vasodilation via stimulation of dopamine 1 (D1) receptors. The efficacy of an intravenous infusion of fenoldopam in decreasing blood pressure in patients with a hypertensive urgency, including patients who developed hypertension after coronary artery bypass graft surgery, and in a small number of patients with hypertensive emergency, is similar to that of sodium nitroprusside. However, unlike sodium nitroprusside, fenoldopam also increases renal blood flow and causes diuresis and natriuresis. There is no evidence of rebound hypertension after stopping the infusion. As the tolerability profile of fenoldopam is generally similar to that of sodium nitroprusside, fenoldopam appears to be an effective alternative to sodium nitroprusside in the immediate treatment of patients who develop severe hypertension and in whom oral treatment is not practical. Fenoldopam may be particularly useful in patients who develop hypertension after coronary artery bypass graft surgery, but further studies are required to confirm its role in hypertensive emergency.

Clarithromycin. A review of its efficacy in the treatment of respiratory tract infections in immunocompetent patients.

Clarithromycin is a broad spectrum macrolide antibacterial agent active in vitro and effective in vivo against the major pathogens responsible for respiratory tract infections in immunocompetent patients. It is highly active in vitro against pathogens causing atypical pneumonia (Chlamydia pneumoniae, Mycoplasma pneumoniae and Legionella spp.) and has similar activity to other macrolides against Staphylococcus aureus. Streptococcus pyogenes, Moraxella catarrhalis and Streptococcus pneumoniae. Haemophilus influenzae is susceptible or intermediately susceptible to clarithromycin alone, but activity is enhanced when the parent drug and metabolite are combined in vitro. Absorption of clarithromycin is unaffected by food. More than half of an oral dose is systemically available as the parent drug and the active 14-hydroxy metabolite. Pharmacokinetics are nonlinear, with plasma concentrations increasing in more than proportion to the dosage. First-pass metabolism results in the rapid appearance of the active metabolite 14-hydroxy-clarithromycin in plasma. Clarithromycin and its active metabolite are found in greater concentrations in the tissues and fluids of the respiratory tract than in plasma. Dosage adjustments are required for patients with severe renal failure, but not for elderly patients or those with hepatic impairment. Drug interactions related to the cytochrome P450 system may occur with clarithromycin use. In addition to the standard immediate-release formulation for administration twice daily, a modified-release formulation of clarithromycin is now available for use once daily. In dosages of 500 to 1000 mg/day for 5 to 14 days, clarithromycin was as effective in the treatment of community-acquired upper and lower respiratory tract infections in hospital and community settings as beta-lactam agents (with or without a beta-lactamase inhibitor), cephalosporins and most other macrolides. Clarithromycin was similar in efficacy to azithromycin in comparative studies and is as effective as and better tolerated than erythromycin. Adverse events are primarily gastrointestinal in nature, but result in fewer withdrawals from therapy than are seen with erythromycin. Clarithromycin provides similar clinical and bacteriological efficacy to that seen with beta-lactam agents, cephalosporins and other macrolides. It offers a cost-saving alternative to intravenous erythromycin use in US hospitals and is available in both once-daily and twice-daily formulations. The spectrum of activity of clarithromycin against common and emerging respiratory tract pathogens may make it suitable for use in the community as empirical therapy of respiratory tract infections in both children and adults.

Adapalene. A review of its pharmacological properties and clinical potential in the management of mild to moderate acne.

Adapalene, a naphthoic acid derivative with retinoid-like activity, is used for the topical treatment of mild to moderate acne vulgaris. It binds to retinoic acid receptors found predominantly in the terminal differentiation zone of epidermis and is more active than tretinoin in modulating cellular differentiation. Adapalene exhibits anti-inflammatory activity in various in vitro and in vivo models. To date, adapalene 0.1% gel and lotion formulations have been compared only with tretinoin 0.025% gel. In these comparisons, adapalene 0.1% aqueous gel was at least as effective as tretinoin and in some studies was significantly better at reducing the numbers of noninflammatory, inflammatory and total facial lesions in patients with mild to moderate acne. In such comparisons, the cutaneous tolerability of adapalene aqueous gel was generally better than that of tretinoin. On the basis of published data, adapalene aqueous 0.1% gel is an effective and generally better tolerated alternative to tretinoin 0.025% gel for the topical treatment of patients with mild to moderate acne.

Cefotaxime. A reappraisal of its antibacterial activity and pharmacokinetic properties, and a review of its therapeutic efficacy when administered twice daily for the treatment of mild to moderate infections.

Cefotaxime is well established as an effective and well tolerated antibacterial drug for 3 times daily parenteral treatment of a variety of moderate to severe infections in hospitalised patients. Its frequency of administration has recently been reassessed with a 12-hourly regimen. Comparative studies in hospitalised patients with nosocomial or community-acquired lower respiratory tract infections, demonstrate the similar clinical and bacteriological efficacy of twice daily cefotaxime 1 or 2 g and the same daily dose of ceftriaxone, usually administered once daily. Cefotaxime 2 g twice daily was also similar in efficacy to ceftriaxone 2 g once daily. Retrospective and post-marketing studies also reveal the similar efficacy of cefotaxime administered twice and 3 times daily, and pharmacoeconomic studies suggest that total direct costs of treatment with cefotaxime compared is similar to that with other third generation cephalosporins in currently used dosage regimens. When administered twice daily, cefotaxime is, thus, an effective antibacterial agent for the treatment of hospitalised patients outside the intensive care unit with a variety of mild to moderate non-CNS infections caused by susceptible organisms. When appropriately administered twice daily there is potential to lower the cost of antibacterial treatment without compromising efficacy.

Ketorolac. A reappraisal of its pharmacodynamic and pharmacokinetic properties and therapeutic use in pain management.

Ketorolac is a nonsteroidal anti-inflammatory drug (NSAID) with strong analgesic activity. The analgesic efficacy of ketorolac has been extensively evaluated in the postoperative setting, in both hospital inpatients and outpatients, and in patients with various other acute pain states. After major abdominal, orthopaedic or gynaecological surgery or ambulatory laparoscopic or gynaecological procedures, ketorolac provides relief from mild to severe pain in the majority of patients and has similar analgesic efficacy to that of standard dosages of morphine and pethidine (meperidine) as well as less frequently used opioids and other NSAIDs. The analgesic effect of ketorolac may be slightly delayed but often persists for longer than that of opioids. Combined therapy with ketorolac and an opioid results in a 25 to 50% reduction in opioid requirements, and in some patients this is accompanied by a concomitant decrease in opioid-induced adverse events, more rapid return to normal gastrointestinal function and shorter stay in hospital. In children undergoing myringotomy, hernia repair, tonsillectomy, or other surgery associated with mild to moderate pain, ketorolac provides comparable analgesia to morphine, pethidine or paracetamol (acetaminophen). In the emergency department, ketorolac attenuates moderate to severe pain in patients with renal colic, migraine headache, musculoskeletal pain or sickle cell crisis and is usually as effective as frequently used opioids, such as morphine and pethidine, and other NSAIDs and analgesics. Subcutaneous administration of ketorolac reduces pain in patients with cancer and seems particularly beneficial in pain resulting from bone metastases. The acquisition cost of ketorolac is greater than that of morphine or pethidine; however, in a small number of studies, the higher cost of ketorolac was offset when treatment with ketorolac resulted in a reduced hospital stay compared with alternative opioid therapy. The tolerability profile of ketorolac parallels that of other NSAIDs; most clinically important adverse events affect the gastrointestinal tract and/or renal or haematological function. The incidence of serious or fatal adverse events reported with ketorolac has decreased since revision of dosage guidelines. Results from a large retrospective postmarketing surveillance study in more than 20,000 patients demonstrated that the overall risk of gastrointestinal or operative site bleeding related to parenteral ketorolac therapy was only slightly higher than with opioids. However, the risk increased markedly when high dosages were used for more than 5 days, especially in the elderly. Acute renal failure may occur after treatment with ketorolac but is usually reversible on drug discontinuation. In common with other NSAIDs, ketorolac has also been implicated in allergic or hypersensitivity reactions. In summary, ketorolac is a strong analgesic with a tolerability profile which resembles that of other NSAIDs. When used in accordance with current dosage guidelines, this drug provides a useful alternative, or adjuvant, to opioids in patients with moderate to severe pain.

Serenoa repens (Permixon). A review of its pharmacology and therapeutic efficacy in benign prostatic hyperplasia.

Serenoa repens (Permixon) has been available for several years for the treatment of men with benign prostatic hyperplasia (BPH). The drug is the n-hexane lipidosterolic extract of the dwarf American palm (also known as Serenoa repens) and is a complex mixture of various compounds. A number of pharmacodynamic effects have been demonstrated with the lipidosterolic extract of Serenoa repens (LSESR), suggesting multiple mechanisms of action including in vitro inhibition of both type 1 and type 2 isoenzymes of 5 alpha-reductase and interference with binding of dihydrotestosterone to cytosolic androgen receptors in prostate cells. In controlled clinical trials in men with BPH, oral administration of Serenoa repens 160 mg twice daily for 1 to 3 months was generally superior to placebo in improving subjective symptoms, such as dysuria, as well as objective parameters. The frequency of nocturia was reduced by 33 to 74%, while urinary frequency during the day decreased by 11 to 43% and peak urinary flow rate increased by 26 to 50% with Serenoa repens. Corresponding values for placebo were 13 to 39%, 1 to 29% and 2 to 35%. The only large comparative trial conducted to date, in which > 1000 men with moderate BPH were randomised to receive Serenoa repens 160 mg twice daily or finasteride 5 mg once daily for 6 months, demonstrated similar efficacy between the two drugs. No statistically significant difference was demonstrated between treatment groups for improvement in patient self-rated quality-of-life scores and the primary end-point of objective symptom score; International Prostate Symptom Score improved by 37% with Serenoa repens compared with 39% with finasteride. In much smaller comparative trials, few significant differences were demonstrated between Serenoa repens and alpha 1-receptor antagonists, and larger randomised trials of adequate duration are required to better compare the clinical efficacy of these drugs. The most frequently reported adverse events in clinical trials with Serenoa repens have been minor gastrointestinal problems (e.g. nausea and abdominal pain). In conclusion, Serenoa repens is well tolerated and has greater efficacy than placebo and similar efficacy to finasteride in improving symptoms in men with BPH. Although there is a need for further comparative studies, particularly with alpha 2-receptor antagonists, available data indicate that Serenoa repens is a useful alternative to alpha 1-receptor antagonists and finasteride in the treatment of men with BPH.

Aceclofenac. A review of its pharmacodynamic properties and therapeutic potential in the treatment of rheumatic disorders and in pain management.

Aceclofenac is a phenylacetic acid derivative with anti-inflammatory and analgesic properties similar to those of diclofenac. However, preclinical studies suggest that the potential of aceclofenac to cause gastrointestinal damage is less than that of diclofenac. Double-blind comparative trials indicate that the efficacy of aceclofenac is at least equivalent to that of ketoprofen and similar to that of indomethacin and diclofenac in patients with rheumatoid arthritis, similar to that of diclofenac and piroxicam in patients with osteoarthritis of the knee and similar to that of tenoxicam, indomethacin and naproxen in patients with ankylosing spondylitis. The analgesic efficacy of aceclofenac 100mg is more prolonged than that of paracetamol (acetaminophen) 650mg. If the apparently improved gastrointestinal tolerability of aceclofenac compared with diclofenac is confirmed by wider clinical experience, aceclofenac will have the potential to become a preferred initial drug in an individualised NSAID regimen in patients with rheumatic disorders.

Cefuroxime axetil. A review of its antibacterial activity, pharmacokinetic properties and therapeutic efficacy.

Cefuroxime axetil is an oral cephalosporin which is rapidly hydrolysed to the active parent compound, cefuroxime. Cefuroxime has a broad spectrum of in vitro antibacterial activity which encompasses methicillin-sensitive staphylococci and the common respiratory pathogens Streptococcus pneumoniae, Haemophilus influenzae, Moraxella (Branhamella) catarrhalis and group A beta-haemolytic streptococci. Cefuroxime has broad spectrum activity against the beta-lactamase positive respiratory pathogens H. influenzae and M. catarrhalis; it is also active against penicillin-susceptible and -intermediate strains of S. pneumoniae. In clinical trials, cefuroxime axetil (administered twice daily) has been evaluated in the treatment of upper and lower respiratory tract infections and has demonstrated similar efficacy to established antibacterial agents, including amoxicillin/clavulanic acid and cefaclor. Five days' treatment with cefuroxime axetil was recently shown to be as effective as 10 days' treatment with either cefuroxime axetil or amoxicillin/clavulanic acid in patients with acute otitis media or acute bronchitis. Cefuroxime axetil was at least as effective as phenoxymethylpenicillin (penicillin V) in the treatment of patients with group A beta-haemolytic streptococcal tonsillopharyngitis. A number of studies have evaluated the efficacy of cefuroxime axetil as the oral component of intravenous to oral sequential therapy in hospitalised patients with lower respiratory tract infection. In each study patients received parenteral cefuroxime for approximately 2 days followed by cefuroxime axetil for 5 to 10 days. In comparative studies, cefuroxime sequential therapy was as effective as amoxicillin/ clavulanic acid sequential therapy and full courses of parenteral cefuroxime, cefotiam or cefoperazone. Adults with urinary tract infections and skin infections were also effectively treated with cefuroxime axetil, as were adults and adolescents with early stage lyme disease. Cefuroxime axetil is associated with a low incidence of adverse events, with gastrointestinal disturbances being the most frequently observed. Thus, cefuroxime axetil is an effective and convenient treatment for a wide range of infections and may be considered a therapeutic option when empirical treatment of community-acquired infections is required. Moreover, given the promising results of several intravenous/oral sequential treatment studies, cefuroxime axetil may also become established as an oral component of sequential treatment regimens.

Verapamil: a review of its pharmacological properties and therapeutic use in coronary artery disease.

Verapamil has well proven efficacy in the treatment of patients with hypertension, and early studies indicated its efficacy in the treatment of coronary artery disease. The efficacy of verapamil relative to placebo in patients with stable angina pectoris is confirmed, and the drug is at least as effective as nifedipine, propranolol or metoprolol and of similar efficacy to bepridil and nicardipine when administered as a conventional or sustained release formulation. Verapamil is the first calcium antagonist to be shown in a double-blind study to significantly reduce mortality and reinfarction rate after acute myocardial infarction in patients without heart failure. In these patients, the reduction in mortality achieved with verapamil was similar to that reported with beta-adrenoceptor antagonists, suggesting that verapamil may be a suitable alternative to beta-blockers as secondary prevention in patients intolerant of these drugs. Recurrence of stenosis in patients who successfully undergo percutaneous transluminal coronary angioplasty (PTCA) limits the usefulness of the procedure. Verapamil has recently been shown to significantly reduce the rate of restenosis in patients with stable angina at risk of recurrence, although these initial results require confirmation. Verapamil, therefore, is effective in the treatment of patients with stable angina pectoris, appears to be an alternative to beta-blockers in selected patients as late start secondary prevention after acute myocardial infarction and has a potential role in preventing recurrent stenosis after PTCA, if initial results are confirmed.

Oral naftidrofuryl. A review of its pharmacology and therapeutic use in the management of peripheral occlusive arterial disease.

Naftidrofuryl has been used for the treatment of intermittent claudication, a symptom of mild to moderate peripheral occlusive arterial disease (POAD), for at least 2 decades. As a serotonin 5-HT2 receptor antagonist, naftidrofuryl has vasoactive properties in addition to its favourable effects on oxidative metabolism, peripheral transcutaneous oxygen pressure and the rheological properties of platelets and erythrocytes. The drug may also reduce hypercholesterolaemia-induced intimal proliferation. Clinical trials which conform best with European guidelines have shown that 3 and 6 months' oral therapy with naftidrofuryl 600 or 633 mg/day (in 3 or 2 divided doses) increased pain-free walking distance to a greater extent than placebo administration in patients with POAD. Surgical revascularisation was required less often during 6 months of therapy with naftidrofuryl than in placebo recipients, confirming the superiority of naftidrofuryl treatment compared with placebo. Available data provide some evidence of efficacy of the drug in the treatment of ischaemic rest pain and vascular ulceration. However, further trials are required before the usefulness of oral naftidrofuryl in severe POAD can be fully established. When given orally, naftidrofuryl is well tolerated. Mild gastrointestinal effects are the most common adverse events, requiring withdrawal of therapy in approximately 1.2% of patients compared with 0.95% of placebo-treated patients. In summary, oral naftidrofuryl improves the symptoms of intermittent claudication in patients with POAD with minimal risk of adverse effects. Therefore, in patients with Fontaine's classification stage II POAD for whom lifestyle modifications and management of concomitant disease have provided insufficient benefit, naftidrofuryl is potentially useful.

Goserelin. A review of its pharmacodynamic and pharmacokinetic properties, and therapeutic use in benign gynaecological disorders.

Goserelin is a gonadotrophin-releasing hormone (GnRH) analogue which, during continuous administration, down-regulates the pituitary-ovarian gonadal axis and reduces levels of the gonadotrophins, luteinising hormone and follicle-stimulating hormone. In women, this results in suppression of ovarian steroidogenesis and a decline in estrogen to levels similar to those observed after menopause or following surgical oophorectomy. Thus, goserelin has a useful role in the management of some benign estrogen-dependent gynaecological disorders. Goserelin is available as a biodegradable sustained release depot 3.6mg injection which is administered every 28 days. In women with endometriosis, monthly injections of depot goserelin were effective in achieving resolution of endometriotic implants and in improving pelvic symptoms, including pain and dyspareunia. Randomised clinical comparisons of depot goserelin with danazol indicate that goserelin is at least as effective as danazol and is better tolerated in the treatment of endometriosis. In the management of uterine leiomyomata (fibroids), goserelin depot injections reduce uterine size and the size of uterine leiomyomata, with maximum clinical benefit achieved approximately 3 to 4 months after initiation of treatment. When used as an adjunctive pretreatment for women undergoing surgical removal of uterine leiomyomata, goserelin was associated with technically easier surgical procedures, reduced intraoperative blood loss and reduced transfusion requirements around the time of surgery. As an alternative to surgery, therapeutic use of goserelin is limited by the rapid regrowth of leiomyomata following cessation of treatment. However, goserelin may be a useful treatment for women approaching menopause, in whom uterine leiomyomata shrink naturally as endogenous estrogen levels decline. In women with dysfunctional uterine bleeding, treatment with depot goserelin before surgery facilitates resection and ablative procedures by suppressing endometrial growth and thinning the endometrial mucosa. Goserelin is also an effective alternative to surgery in this patient group. As adjuvant therapy for women undergoing assisted reproduction procedures, goserelin is associated with reduced cycle cancellation rates and with an increase in the rate of oocyte retrieval. The tolerability profile of goserelin is characterised by adverse effects typical of hypoestrogenism, including hot flushes, loss of libido and loss of bone mineral density. However, concomitant 'add-back' hormone replacement therapy appears to effectively reduce these hypoestrogenic symptoms. In summary, the availability of depot goserelin has broadened the spectrum of effective treatments for benign estrogen-dependent gynaecological disorders. As goserelin is effective as a sustained release depot formulation suitable for administration on a monthly basis, it is also a convenient and practical treatment choice.