[New drugs for horses and production animals in 2010]. / Neue Arzneimittel für Pferde und landwirtschaftliche Nutztiere 2010.

In 2010, three new active pharmaceutical ingredients were released on the German market for horses and food-producing animals. These were gamithromycin (Zactran®), a new macrolide antibiotic, Monepantel (Zolvix®), a broad spectrum anthelmintic with a novel mechanism, and Pergolide (Prascend®), the first dopamine receptor agonist for animals. Two substances have been approved for additional species. The tetracycline antibiotic doxycycline is now also authorized for turkeys and the nonsteroidal anti-inflammatory drug firocoxib from the group of cyclo-oxygenase-2 (COX-2) inhibitors is now available for horses. Furthermore, four new preparations with an interesting new pharmaceutical form, one drug with a new formulation and two drugs, which are interesting because of other criteria, were added to the market for horses and food producing animals.

Effects of compounding and storage conditions on stability of pergolide mesylate.

OBJECTIVE: To determine the effects of temperature and light over a 35-day period on stability of pergolide mesylate after compounding in an aqueous vehicle. DESIGN: Evaluation study. PROCEDURES: Pergolide was compounded into a formulation with a final target concentration of 1 mg/mL. Aliquots of the formulation were then stored at -20 degrees, 8 degrees, 25 degrees, or 37 degrees C without exposure to light or at 25 degrees C with exposure to light for 35 days. Samples were assayed in triplicate by means of high-pressure liquid chromatography immediately after compounding and after 1, 7, 14, 21, and 35 days of storage. RESULTS: Mean+/-SD concentration of pergolide in the formulation immediately after compounding was 1.05+/-0.086 mg/mL. Samples exposed to light while stored at 25 degrees C had undergone excessive degradation by day 14, samples stored at 37 degrees C had undergone excessive degradation by day 21, and samples stored at 25 degrees C without exposure to light had undergone excessive degradation by day 35. The decrease in expected concentration corresponded with the appearance of degradation peaks in chromatograms and with a change in color of the formulation. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that pergolide mesylate was unstable after compounding in an aqueous vehicle and that storage conditions had an effect on stability of the compounded formulation. Compounded pergolide formulations in aqueous vehicles should be stored in a dark container, protected from light, and refrigerated and should not be used >30 days after produced. Formulations that have undergone a color change should be considered unstable and discarded.

A comparison of the efficacy and safety of pergolide and bromocriptine in the treatment of hyperprolactinemia.

UNLABELLED: Pergolide is a synthetic ergoline derivative with highly potent long-acting PRL-lowering activity, allowing therapy of hyperprolactinemia with a once daily administration of the drug. The results of two open-label, randomized controlled multicenter clinical trials are reported. Pergolide (taken once a day), was compared with bromocriptine (taken two to four times daily) regarding efficacy and safety in the reduction of PRL levels, the cessation of galactorrhea and amenorrhea, the improvement in sexual function, and tumor shrinkage in hyperprolactinemia without (trial I; 61 patients) and with radiologically evident pituitary tumors (trial II; 96 patients). Both drugs were equally effective in lowering PRL levels in both trials. A median optimal dose of 50 micrograms pergolide and 5 mg bromocriptine/day suppressed PRL levels in the 61 patients of trial I by more than 80%. During the 24-week investigational period galactorrhea disappeared in 96% and 87% of patients, whereas menstruation returned in 90% and 96% of patients, respectively. An equally high efficacy (optimal median dose: 75-100 micrograms pergolide, 7.5-10 mg bromocriptine daily) was observed in trial II, although the resumption of menses was less frequent than in the patients of trial I (50% and 58% of patients, respectively). Sexual dysfunction improved similarly on both drugs in about half the patients. In addition, tumor shrinkage occurred to a similar extent with both drugs. A high incidence of adverse events was noted especially at the initiation of therapy with both compounds: nausea, dizziness, vomiting, asthenia, headache, and decrease in blood pressure occurred at a similar incidence and extent during the use of pergolide and bromocriptine. Patients in trial I treated with pergolide reported a slightly higher incidence of fever, vasodilatation, and flu syndrome. CONCLUSIONS: in these 24-week studies comprising a total of 157 hyperprolactinemic patients, a once daily administration of pergolide was shown to be as safe and effective as the two to four times daily ingestion of bromocriptine. Longer-acting dopamine agonists like pergolide that can be taken once daily, are likely to increase the ease to adherence to the therapeutic regimen. This might result in a higher compliance to medical treatment of hyperprolactinemia.