Isis Pharmaceuticals Inc. received a $3 million milestone payment from GlaxoSmithKline PLC for starting a study that ties into its partnership to develop three new drugs using Isis’ proprietary antisense technology.

The news only impacted Isis’ stock value incrementally, as it grew 7 cents and closed at $25.53 May 15. Isis’ stock has, however, taken a tumble in recent months, thanks in part to a general cooling of a once-hot biotech market but also because the company’s first quarter results disappointed analysts.

CEO Stanley Crooke attributed the 35 percent drop in revenue — to $28.2 million in the quarter ended March 31, 2014 compared with $43.4 million revenue in the like quarter of 2013 — to a decrease in milestone payments.

Milestone revenue decreased from $41.7 million in last year’s first quarter to $19.6 million in this year’s first quarter; licensing and royalty revenue for the first quarter rose, however, to $8.6 million from just $1.7 million last year.