Troubled drugmaker Amgen has received a subpoena from the New York attorney general seeking documents related to promotional and other activities, according to a May 22 regulatory filing.

The subpoena seeks documents related to Amgen’s sales and marketing activities, medical education, clinical studies, pricing and contracting license and distribution agreements and corporate communications, according to a filing with the US Securities and Exchange Commission. Amgen received the subpoena May 10.

The biotech firm also said in published reports that the US Senate Finance Committee sent a letter to the company May 16 requesting a briefing to discuss media reports related to the marketing and safety of erythropoiesis stimulating agents, also referred to as EPO drugs.

Earlier this month, The New York Times ran an exposé about “hundreds of millions of dollars” in payments Johnson & Johnson and Amgen make each year to cancer physicians, dialysis centers and other big users of J&J’s Procrit and Amgen’s Aranesp. The payments are legal, noted The Times, but few outsiders know their real size and critics claim the cash influences doctors to over-prescribe the drugs. Over the last few years, the report added, the payments have risen as the companies compete for market share.

Potentially adding to Amgen’s woes, an outside advisory panel to the FDA voted earlier this month to put additional restrictions on the labels of EPO drugs. Among the recommendations, the committee voted 12 to 5 that the drugs should be barred from use by patients with certain types of cancer until more is known about their safety; 15 to 2 that there should be more restrictions in general if the drugs remain on the market; and 17 to 0 that more studies were needed. That last vote—to conduct additional studies—might turn out to be very costly and time-consuming for the firms. The FDA typically follows its panel’s advice but is not bound to do so.

Last year, Aranesp had sales of $4.1 billion, while its other anti-anemia drug, Epogen, had sales of $2.5 billion. They accounted for 46% of Amgen’s 2006 revenue.