Earlier this month, vTv Therapeutics announced positive phase two results for its oral antidiabetic drug, TTP-399, when used as an adjunct therapy to insulin in type one diabetes (T1D) patients.
Although vTv Therapeutics has conducted clinical trials testing its liver-selective glucokinase (GK) activator in type two diabetes (T2D) patients, the company has shifted its efforts towards developing the drug for T1D. If TTP-399 can show potential in allowing certain subsets of T1D patients to gain better glycemic and weight control, as well as potentially lower daily insulin dosages, the company has a chance to become a strong player in the developing market.
The multi-centre, randomised, double-blind, phase two Simplici-T1 study examined TTP-399 as an adjunct therapy to insulin in T1D patients. The study revealed that TTP-399 was effective in reducing haemoglobin A1c (HbA1c) compared to placebo at 12 weeks in T1D patients on insulin (p=0.03). The first-in-class therapy works by conferring an insulin-independent mechanism of action and targets GK activation in the liver.
The highly competitive and saturated oral drug market for treating T2D patients is pushing some diabetes drug developers, like vTv, to focus more on T1D. Even among the T2D drug classes that were historically only administered by injection, the rise of Novo Nordisk’s oral glucagon-like peptide-1 receptor agonist, Rybelsus (semaglutide), makes it increasingly difficult for new oral therapies to enter the crowded market.
But despite shifting away from the intense competition within the T2D market, TTP-399 will still have to compete against competitor drugs in the T1D arena, as the sodium-glucose cotransporter (SGLT) inhibitors are also striving to gain a foothold in the T1D oral treatment space.
Historically, SGLT inhibitors have been approved and marketed for T2D patients but in March 2019 AstraZeneca’s Forgixa (dapagliflozin) was the first SGLT inhibitor to be approved for use in T1D in Europe. In Japan, Forxiga was the second in its class to be approved for T1D, as Astellas Pharma’s Suglat (ipragliflozin) had already received approval in December 2018. In May 2019, Zynquista (sotagliflozin) gained approval for use in T1D in Europe.
No SGLT inhibitor has been able to gain FDA approval in a T1D indication so far, leaving the oral T1D treatment space wide open in the US. Additionally, Simplici-T1 showed that there were no cases of diabetic ketoacidosis in the TTP-399-treated and placebo-treated groups, indicating that this could be a point of major differentiation and competitive advantage due to worries over increased risk of diabetic ketoacidosis in patients receiving SGLT inhibitor treatment, a concern echoed by key opinion leaders (KOLs) interviewed by GlobalData.