Methodology of monitored release of a new preparation: buprenorphine

Transdermal buprenorphine in the management of persistent pain - safety aspects

By virtue of their efficacy, opioid analgesics have long been used for the treatment of both acute and chronic pain. Concerns regarding their safety and tolerability have frequently prevented this class of drugs achieving their full therapeutic potential, and their reported association with drug abuse and dependence has led to a reduced acceptance by many patients. Indeed, there is a variety of opioid-like side effects which are common to all members of the class, but some opioids have a more favourable safety profile than others. Buprenorphine is a semisynthestic opioid with a mu-agonistic and kappa-antagonistic receptor-binding profile. Studies over the past two decades have shown buprenorphine to have a complex and unique pharmacological profile, which results in enhanced therapeutic benefits combined with a favourable safety profile. Having been underused before, the development of a new transdermal drug delivery system for buprenorphine has revived interest in this substance. Transdermal buprenorphine (Gruenenthal GmbH, Aachen, Germany) provides a noninvasive method of rate-controlled drug release ensuring constant and predictable serum buprenorphine levels over a prolonged period. This preparation has been shown to be advantageous for long-term treatment of chronic pain patients providing reliable pain control, few adverse events, and good patient acceptance.

European postmarketing surveillance of ramipril in hypertension. 1. Feasibility and study cohort

A prospective observational cohort study of the angiotensin inhibitor, ramipril, was undertaken in four countries within the European Community-Netherlands, United Kingdom, Germany and Belgium. A total of 10,377 consecutive patients with essential hypertension were recruited to the study with the aim of follow-up for one year. Overall 37% of doctors who agreed to participate in the study actually enrolled at least one patient. One third of the doctors who enrolled patients in the study entered two thirds of patients studied. Some 15% of participating males and 27% of females were aged over 70 years. Newly diagnosed hypertensives comprised 22% of the study cohort, the proportion being highest in UK and Netherlands, whereas 53% were established hypertensives of two or more years' duration, the proportion being highest in Germany and Belgium. There were substantial differences among the participating countries in the concurrent treatment these patients were receiving for hypertension, with two or more co-therapies being most frequent in Germany and Belgium. There were also substantial differences in co-therapies for concurrent diseases among the participating countries, reflecting both standard therapeutic practices in local areas and differences in marketing of drugs in the different countries. This report describes the initial findings of this multinational study and emphasises the need to consider several major potentially confounding variables in the analysis of the outcome events both in this study and in other collaborative observational international monitoring schemes for adverse drug reactions.

[Risk evaluation of oxygen desaturation after buprenorphine or morphine administration during the early postoperative period]

The purpose of this study, conducted in a PACU in the early recovery period of orthopaedic procedures under general anaesthesia, was to compare the time course of O2 arterial saturation (SpO2), measured by pulse oximetry, after the intramuscular administration of either buprenorphine (0.30 mg) or morphine (10 mg). The rate of patients who had an episode of O2 desaturation (defined as a SpO2 under 95%) was similar in both groups: 73% after buprenorphine vs 67% after morphine. The cumulative duration of desaturation episodes was higher following buprenorphine (p < 10(-5). Finally, in patients who had at least one episode of arterial desaturation, the mean duration of these episodes was identical in both groups. However the average number of episodes per patient was significantly higher in the buprenorphine group. These results should lead us to be cautious with the use of buprenorphine during the early recovery period, especially as this as this agent has specific characteristics such as a long duration of action and resistance to naloxone.

Buprenorphine in opiate withdrawal: a comparison with clonidine

Clinical efficacy of buprenorphine in controlling withdrawal symptoms was compared against clonidine among 44 opiate dependent males. Subjective and objective withdrawal symptoms were assessed by withdrawal rating scales daily for 10 days. The subjects were randomly assigned to fixed dose schedule of either buprenorphine (0.6-1.2 mg per day, sublingually) or clonidine (0.3-0.9 mg per day, oral) for 10 days. Buprenorphine was found superior to clonidine in alleviating most of the subjective and objective opiate withdrawal symptoms. Subjective symptoms declined earlier among the subjects receiving buprenorphine. No untoward side-effects of buprenorphine were noticed.

Postmarketing surveillance of captopril for hypertension

1. A scheme for augmented spontaneous reporting of adverse drug events using advanced view data systems was developed and applied to study 67,698 consecutive patients prescribed captopril in general practice for the treatment of hypertension. 2. Captopril was an effective hypotensive agent in this population, as only 1.9% of patients were withdrawn because of apparent inefficacy. 3. Adverse effects of captopril resulted in withdrawal of treatment in 8.9% of recipients, and such effects were more frequent in elderly and female recipients. 4. Skin reactions--usually maculopapular rashes--tended to occur early during therapy whereas cough occurred much later and was reported more frequently in non-smokers. 5. Some 1.1% of recipients died during follow-up. There was no evidence of any unusual or unexpected causes of death which might be partially or totally captopril-related in the study cohort. 6. The study confirms the feasibility of large scale postmarketing surveillance studied in general practice and allowed risk benefit assessments to be made on the use of captopril for treating hypertension.

Post marketing surveillance of captopril (for hypertension): a preliminary report

1 The methodology and interim results of a post marketing surveillance of captopril, the first orally active angiotensin converting enzyme inhibitor are presented. 2 Utilising viewdata technology, details of hypertensive patients were entered directly into a mainframe computer. This allowed day to day monitoring of events; a facility not available with paper-based methods. 3 The design of the study allowed analysis of results including some details of efficacy, concomitant therapy, any disease symptoms and reasons for withdrawal. These factors could be categorised according to sex and age. 4 This preliminary report is based on the first 13,295 patients entered from July 1983 with follow-up until January 1985. The results of the study confirm the safety of captopril in the patients studied.

Review of adverse reactions associated with cinoxacin and other drugs used to treat urinary tract infections

The evaluation of adverse drug reactions (ADR) in clinical practice is difficult and imprecise. Establishing a causal relationship may not be possible, and data on incidence cannot be obtained because the number of patients treated is not known. This article describes the ADR reported during the clinical trial program of cinoxacin, a synthetic antibacterial drug used to treat urinary tract infections. Results from 2,801 patients who received cinoxacin showed that 5 per cent reported ADR that were probably or definitely drug induced, and 10 per cent reported ADR in which the relationship was uncertain. There was no relationship between number of reports and patient's age, drug dose, or duration of treatment. Adverse drug reactions affecting the gastrointestinal system were reported by 5.5 per cent of the patients, those involving the central nervous system by 4.3 per cent, and hypersensitivity reported by 2.4 per cent. In the comparative studies, patients treated with cinoxacin reported fewer ADR than those treated with nalidixic acid, furadantin, amoxicillin, or trimethoprim-sulfamethoxazole. Although problems in the assessment and evaluation of ADR still exist, it is hoped that the results from the formal trial program will be representative of those seen in clinical practice.

A comparative study of intramuscular buprenorphine and morphine in the treatment of chronic pain of malignant origin

1 Twenty-seven patients with moderate to severe chronic pain of malignant origin received buprenorphine (0.3 mg) and morphine (10 mg) intramuscularly in a double-blind, single dose within patient study. 2 Efficacy analysis demonstrated no significant differences in the peak analgesic effects or in the time to reach these effects. However, buprenorphine had a significantly longer duration of action than morphine. 3 Sedation was the most frequent unwanted effect with a similar incidence following each treatment. Buprenorphine was associated with a significantly higher incidence, greater severity, earlier onset, and longer duration of dizziness, nausea and vomiting than morphine. 4 Following both treatments there were small but significant decreases in pulse rate, blood pressure, and respiratory rate.

Buprenorphine in postoperative pain: results in 7500 patients

Buprenorphine, a partial opiate-receptor agonist with potent analgesic properties, was given to 7548 patients in the immediate postoperative period. Ninety per cent of patients had good or adequate pain relief for at least 4 hours; there were few adverse effects and the incidence of drug-associated respiratory depression was estimated at less than 1%. There were no other side-effects of clinical note.

The monitored release of buprenorphine: results in the young

Temgesic Injection (buprenorphine), a potent analgesic agent, was given to 240 patients under 18 years of age during a year of monitored release. All but four had the product for the management of moderate or severe pain in the immediate post-operative period. Analgesia was reported as adequate or good in 90% of these young patients when it was assessed 2 and 4 hours after infection. There were no reports of side-effects commonly associated with strong analgesics and particularly antagonist-analgesics such as confusion, hallucination, blurred vision, dry mouth and lightheadedness. There were no serious respiratory or cardiovascular effects. The incidences of other events did not differ from those recorded in the much larger adult population of almost 8,000 patients. Buprenorphine is an effective analgesic suitable for use in the young post-operative patient.