HIV-Resistenzen in Afrika – Wirksamkeit antiretroviraler Substanzen

Seit fast einer Dekade steht in Afrika antiretrovirale Therapie zur Behandlung der HIV-Infektion zur Verfügung. Derzeit sind mehr als 8 Mio. Menschen in Entwicklungsländern in Therapie und zumindest 7 weitere Mio. benötigen diese dringend. Dem hohen Bedarf stehen eingeschränkte Möglichkeiten der Therapieüberwachung sowie ein Mangel an medizinischen Fachkräften, eine schwache Infrastruktur und regelmäßige Unterbrechungen des Nachschubs an Medikamenten gegenüber. Hohe virologische Versagerraten und eine rasche Zunahme von Medikamentenresistenzen sind die Folge. Diese gefährden nicht nur die Gesundheit des Individuums, übertragene Resistenzen bedrohen auch die Wirksamkeit von derzeit empfohlenen Erstlinientherapien und somit den Erfolg von gesamten Programmen. So tragen in Ostafrika bereits über 7 % der therapienaiven Menschen ein Virus, das gegenüber der Klasse der NNRTI resistent ist. Diese Zahl steigt jährlich um fast 30 %. Neben einem virologischen Monitoring zur Früherkennung eines Therapieversagens mit dem Risiko einer Resistenzentstehung scheint auch eine Surveillance der landesspezifischen Resistenzsituation und ein Umdenken bezüglich eines früheren Einsatzes von Proteaseinhibitoren notwendig.

Almost a decade has passed since antiretroviral roll-out commenced in Africa. At present, more than 8 million living with HIV/AIDS in low and middle income countries are receiving ART and an additional 7 million are in need. Limited possibilities of therapy monitoring, a lack of trained staff, a weak infrastructure, and interrupted medication supply chains are common barriers to successful implementation of ART scale-up. High virological failure rates have been observed and the majority of patients failing on therapy develop clinically significant drug resistance which are associated with increased morbidity and mortality and if transmitted pose further threat to existing ART programs. At present more than 7 % of HIV infected people harbor a virus with resistance mainly against the class of NNRTI and to a lesser extent NRTI. This number is constantly rising. Virological monitoring is crucial to detect therapeutic failure early before resistance develops. Enhanced surveillance for drug resistance is important to keep country specific recommendations regarding antiretroviral first-line therapies and an earlier use of protease inhibitor based therapies up-to-date.

Key words

HIV infection - Africa - antiretroviral therapy - acquired drug resistance - transmitted drug resistance

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