There are also obstacles to accessing other arvs , such as efavirenz and d4t , which are both also used in first - line treatment 除了拉米夫定，病人也难以得到其他种类的抗病毒药物，如依非韦伦及司他夫定这两种同样是第一线的抗病毒药物。
2.
The first is under patent in china and is only available at a very high price , putting it out of reach of government treatment programmes and most patients . the second , d4t , is not available in the right dosages for treating people with low bodyweight 前者在中国受专利权限制，令价格非常昂贵，国家的治疗计画不能负担，病人因此不能受惠；后者则未有适合体重较轻病人所用的剂量，令他们用药时较麻烦。
3.
In many countries , fixed - dose combinations of these arvs are available . for example , one of the most commonly used aids drug combinations in developing countries is a triple fdc containing 3tc , d4t and nvp taken as one pill twice a day . fdcs simplify treatment by significantly reducing the number of pills that need to be taken daily 很多国家都有抗爱滋病毒药物固定剂量组合的供应，例如其中一种在发展中国家最常用的爱滋病复合药物是三合一固定剂量组合，即一颗药丸内含三种成分：拉米夫定（ 3tc ） 、司他夫定（ d4t ）及奈韦拉平（ nvp ） ，病人只需每日服药两次，每次一颗。
