Annovis Bio has announced positive Phase III trial data indicating that its drug candidate, buntanetap (formerly ANVS401 or Posiphen), improves cognition in a subgroup of patients with Parkinson’s disease. The Pennsylvania-based company's stock price surged following the announcement of these results.
The data, derived from a subgroup analysis of a Phase III trial, revealed significant improvements in MDS-UPDRS Part II, Part III, and Phase II+III scores for patients diagnosed with Parkinson’s for more than three years who received a 20mg dose of buntanetap, compared to those on placebo and baseline measurements. Another subgroup analysis showed notable improvements in MDS-UPDRS scores in patients with postural instability and gait difficulty (PIGD), a subset known for faster disease progression.
The company had initially designated MDS-UPDRS Part II+III as the primary endpoint but shifted focus to Part II following FDA feedback, which deemed it more reflective of clinically relevant changes. Consequently, MDS-UPDRS Part III became a secondary outcome measure. Buntanetap met both endpoints in patients diagnosed for over three years.
The Phase III trial (NCT05357989) enrolled 523 patients who were administered either 10mg or 20mg of buntanetap or a placebo. Buntanetap functions by inhibiting the formation of neurotoxic proteins such as amyloid beta, tau, alpha-synuclein, and TDP43. Its mechanism of action aims to reverse neurodegeneration in Parkinson’s and Alzheimer’s diseases by enhancing synaptic transmission and reducing neuroinflammation.
Annovis Bio's CEO, Maria Maccecchini, stated, "These compelling data reinforce our commitment to advancing buntanetap into a longer study, which will allow us not only to verify observed symptomatic improvements but also to explore buntanetap’s disease-modifying properties."
Previous Alzheimer's Trial Data
In April 2024, Annovis Bio shared data from a Phase II/III clinical trial of buntanetap in Alzheimer’s disease (NCT05686044). This trial, involving 320 patients, failed to meet a co-primary endpoint, leading to a decrease in the company's stock price. Annovis also reported a patient screening issue, noting that the initial recruitment did not include pre-screening for Alzheimer’s biomarkers in plasma. Despite this, Annovis plans to proceed with a Phase III trial.
