Earlier this year, Allergan’s Linzess and Takeda’s Amitiza gained a new competitor in Synergy’s Trulance. But just as the newcomer was settling into challenge mode, Express Scripts has dealt it a serious blow.

Just a little more than four months into its launch, the med has received the cold shoulder from Express Scripts, which excluded it from its national preferred formulary for 2018. Instead, the PBM says, it prefers either of the older meds as options for chronic idiopathic constipation, the approval Trulance bears, or IBS-C, an indication Synergy is currently chasing.

RELATED: Synergy's Trulance wins an OK to battle Allergan's Linzess in CIC—and IBS-C could be next

Some analysts liked the $353-per-script price tag Synergy slapped on the newcomer; it matched Linzess’ and came in just a tad above Amitiza’s $350-per-script cost, boding well for "adoption among patients, payers and physicians," Oppenheimer’s Derek Archila wrote to clients at the time. In May, Synergy said it was already poaching patients from other drugmakers, with about half of scripts at that point going to those who’d been on other branded medications.

Express Scripts, though, may have been looking for a bigger discount, as PBMs are wont to do. Just look at how fellow new launch Tymlos, a bone drug from Radius that undercut its competition, fared: Express Scripts listed it as a preferred med, kicking off fixture Forteo from Eli Lilly to make space.

RELATED: Synergy preps for Trulance launch with competitive pricing, experienced GI reps

Now, it’ll be up to Synergy’s field force of 250 reps to help navigate around the setback. They’re currently targeting a prescriber base of 27,000 gastroenterologists, primary care physicians, nurse practitioners and physician assistants, the company said in May.