GlaxoSmithKline said Thursday that it paid more than 5,000 US healthcare professionals a total of $56.8 million last year for promotional talks or serving on advisory boards. It gave another $28.5 million to institutions for their help in conducting research.

The company has been posting payments to physicians for peer-to-peer education programs and consulting services since the second quarter of 2009. In the last nine months of 2009, GSK paid $51 million to US doctors. The company has not previously reported payments for research.

Under pressure for more transparency about such practices, several drug makers have voluntarily disclosed payments to doctors, hospitals and other medical professionals. The payments can influence providers’ decisions about drugs, critics charge.

On Wednesday, Merck said it paid $20.4 million last year to more than 2,000 US doctors and healthcare professionals. Today, Pfizer disclosed $177 million in payments to nearly 200,000 healthcare professionals, with 61% of that having gone to clinical trials “and related research and development expenses.”

Come 2013, companies will have to make the disclosures for payments made in 2012 under the Affordable Care Act’s sunshine provision.

GSK also provided more details about its CME program, saying four additional organizations were picked to submit grants in 2011, in addition to the 20 selected in 2010, and that the first grants were awarded mid-year under its new funding process. Executive summaries of the approved grant proposals were posted but not amounts.

The new medical education funding process went into effect on Jan. 1, 2010, limiting grants to academic medical centers and medical societies with accreditation, but shutting out support for CME by commercial providers including medical education and communication companies (MECCs).