GlaxoSmithKline ( GSK) and Boehringer Ingelheim are the latest drugmakers to bolster the battle against the spread of HIV and AIDS, announcing a collaboration to simplify treatment options for people in developing countries. The two companies on Monday said they have signed a letter of intent for an accelerated development program to co-package Combivir and Viramune to treat HIV infection in the developing world. Both companies hope to streamline the treatments available and increase access to antiretrovirals. GlaxoSmithKline and Boehringer have contacted the Food and Drug Administration on the development of the co-package of the two drugs, using draft guidance designed to increase treatment options for the developing world. Shares of GlaxoSmithKline fell 53 cents, or 1.3%, to $40.22. "The co-package of Viramune and Combivir is the most expeditious strategy for facilitating access to HIV treatment in the developing world. In practice, the Viramune-Combivir co-package will facilitate distribution and delivery of a recognized triple therapy to patients in need," said Alessandro Banchi, chairman at Boehringer. A wave of new studies shows HIV continues to spread virtually unchecked in some regions. Last week, Gilead Sciences ( GILD) cut the price of its HIV-fighter Viread by 37% to select countries.