A Senate committee is requesting documents and information on drug pricing from Valeant Pharmaceuticals and three other drug companies in the wake of several high profile prescription drug price hikes.

The Senate’s special committee on aging has also requested documents from Turing Pharmaceuticals, Retrophin Inc., and Rodelis Therapeutics. Each request focuses on drugs that have seen recent and significant spikes in price.

The move comes amid public outcry over recent drug price hikes, most notably Turing’s move to raise the price of Daraprim by 5,000 percent after obtaining rights to the drug. The drug is the only U.S.-approved treatment for a deadly parasitic infection called toxoplasmosis.

Valeant is under a spotlight over its general business practices, which involve buying smaller drug developers and then hiking prices on their medicines.

The committee tentatively plans a hearing December 9.

(AP)