TD 8954 (also known as TAK 954) is a selective serotonin 5-HT(4) receptor agonist. It is known a potential role for potent and efficacious 5-HT(4) receptor agonists in the treatment of Alzheimer's disease (AD). TD 8954 participated in phase I clinical trials to study its potential role in the treatment of AD. However, this study was discontinued. In addition, TD 8954 is involved in phase II clinical trials to investigate its effect on gastrointestinal and colonic transit in diabetic or idiopathic gastroparesis participants and for the prophylaxis and treatment of postoperative gastrointestinal dysfunction in participants undergoing large- and small-bowel resection.

Axelopran (previously known as TD-1211), a peripherally selective, multivalent µ-opioid receptor antagonist that is under development by Theravance Biopharma. This drug participated in phase II clinical trials in subjects with opioid-induced constipation. The most common adverse events were abdominal pain, nausea, and diarrhea. There were no indications of opioid withdrawal effects or reductions in opioid analgesia in patients treated with axelopran.

Axelopran (previously known as TD-1211), a peripherally selective, multivalent µ-opioid receptor antagonist that is under development by Theravance Biopharma. This drug participated in phase II clinical trials in subjects with opioid-induced constipation. The most common adverse events were abdominal pain, nausea, and diarrhea. There were no indications of opioid withdrawal effects or reductions in opioid analgesia in patients treated with axelopran.