The approach of new transparency rules, coupled with patent losses and industry’s shift to specialty meds, has contributed to a big drop in the amount drugmakers are spending on promotional speaking, says ProPublica.

The nonprofit’s March analysis showed that, with the exception of a few firms like Johnson & Johnson, which boosted spending by 17% from 2011 to 2012 as it launches new products for diabetes and blood-thinning, most of the companies tracked have cut their outlays.

Over that same one-year period, Eli Lilly’s checks to speakers fell by 55%, from $47.9 million to $21.6 million; Pfizer’s dropped by 62%, from nearly $22 million to $8.3 million; and GlaxoSmithKline’s slid by 61% to $9.3 million, vs. $24 million. Novartis, the largest drugmaker by US sales in 2012, slashed payouts by 40% to $14.8 million from $24.8 million between October 2010 and September 2011.

As to why industry is shelling out less for peer-to-peer talks by HCPs, ProPublica says one factor is the approach of transparency rules enacted by the Physician Payment Sunshine Act.

Then there’s the patent cliff—no new medicines to launch means fewer educational dollars for docs. Also driving it, says ProPublica, is the shift from mass-market drugs toward specialty products prescribed by fewer physicians, the latter requiring less sales support and, possibly, lower payments overall.