Posaconazole

Absorption

Posaconazole is absorbed with a median Tmax of approximately 3 to 5 hours.

Toxicity

During the clinical trials, some patients received posaconazole up to 1600 mg/day with no adverse events noted that were different from the lower doses. In addition, accidental overdose was noted in one patient who took 1200 mg BID for 3 days. No related adverse events were noted by the investigator.

Description

Posaconazole, launched in the UK, is the newest member of the azole class of antifungal agents to reach the market. It is indicated for the treatment and prophylaxis of a range of invasive fungal infections, including aspergillosis,fusariosis, chromoblastomycosis, mycetoma, and coccidiomycosis in patients who are refractory to, or intolerant of, standard therapy with amphotericin B and/or itraconazole. In the US, it is approved for the prophylaxis of invasive Aspergillus and Candida infections in patients 13 years of age who are at high risk of developing these infections due to being severely immunocompromised. Additionally, it is approved for the treatment of oropharyngeal candidiasis. Posaconazole has an expanded spectrum of activity over other members of the azole antifungals. In addition to potent activity against refractory cases of aspergillosis and fluconazole-resistant Candida, it demonstrates activity against Zygomycetes.

Description

Posaconazole is an antifungal drug that was developed by Schering-Plough in the mid-2000s and is marketed under the trade names Noxafil and Posanol. It may be more effective than the older drug fluconazole, but it may also have more serious side effects, such as prolonged heart QT interval. Posaconazole is in?Phase II clinical trials for treating Chagas disease, but its ultimate cost may be too high for sufferers of this disease.

The Uses of Posaconazole

Posaconazole is a sterol C14ɑ demethylase inhibitor with an IC50 of 0.25 nM

Background

Posaconazole is a triazole antifungal drug that is used to treat invasive infections by Candida species and Aspergillus species in severely immunocompromised patients.

Indications

For prophylaxis of invasive Aspergillus and Candida infections in patients, 13 years of age and older, who are at high risk of developing these infections due to being severely immunocompromised as a result of procedures such as hematopoietic stem cell transplant (HSCT) recipients with graft-versus-host disease (GVHD), or due to hematologic malignancies with prolonged neutropenia from chemotherapy. Also for the treatment of oropharyngeal candidiasis, including oropharyngeal candidiasis refractory to itraconazole and/or fluconazole. Posaconazole is used as an alternative treatment for invasive aspergillosis, Fusarium infections, and zygomycosis in patients who are intolerant of, or whose disease is refractory to, other antifungals.

What are the applications of Application

Posaconazole is a triazole anti-fungal

Pharmacokinetics

Posaconazole is an antifungal agent structurally related to itraconazole. It is a drug derived from itraconzaole through the replacement of the chlorine substituents with flourine in the phenyl ring, as well as hydroxylation of the triazolone side chain. These modifications enhance the potency and spectrum of activity of the drug. Posaconazole can be either fungicial or fungistatic in action.

Metabolism

Posaconazole primarily circulates as the parent compound in plasma. Of the circulating metabolites, the majority are glucuronide conjugates formed via UDP glucuronidation (phase 2 enzymes). Posaconazole does not have any major circulating oxidative (CYP450 mediated) metabolites. The excreted metabolites in urine and feces account for ~17% of the administered radiolabeled dose.