McNeil Consumer & Specialty Pharmaceuticals, a division of Johnson & Johnson, told Icagen on Thursday that it was ending its drug development group with the Durham biopharmaceutical firm.

McNeil had been under contract to pay Icagen $48 million plus royalties if the drug they were co-developing to combat sickle cell disease won FDA approval.

Phase III trials of the drug were terminated in April due to poor results.

Icagen (NASDAQ: ICGN) fell 15 cents to $1.75 in after-hours trading.

The drug was known as senicapoc.

Icagen said in a statement that it would continue to analyze data and seek future options for the drug.