On 20 May, Annovis Bio announced positive results from a double-blind, placebo-controlled Phase IIa trial evaluating the safety and tolerability of its pipeline asset ANVS401 (posiphen) in patients with early Parkinson’s disease (PD). The data showed a highly statistically significant reduction in the levels of a number of different inflammatory biomarkers in patients who were given ANVS401. The announced data further strengthen the previous interim trial findings announced in March, where ANVS401 showed an improvement in the speed, coordination and overall motor skill functions scores of PD patients with no serious adverse events.
GlobalData believes that while the early, preliminary data generated so far are promising and there is an established unmet need for novel treatment approaches in this space, concerns around the drug’s ability to provide therapeutic benefits in larger Phase III trials and the expected high cost of a first-in-class potential therapy will impact its future market entry. Given that, GlobalData anticipates that ANVS401 will generate sales of $161m in 2027 in the US if approved.
ANVS401 is a small molecule that targets α-synuclein and is administrated orally. In the clinical trial, the drug demonstrated a reduction of the levels of α-synuclein that form Lewy bodies, a hallmark pathological factor in PD. It also affects other toxic proteins such as amyloid and tau protein tangles involved in neurodegenerative disorders, primarily Alzheimer’s disease (AD). The reduction of these toxic proteins is believed to decrease neuroinflammation, enhance axonal nerve transport and protect the neurons from dying. The new data from the ANVS401 Phase IIa trial showed that the drug reduced four prognostic inflammatory markers involved in PD and AD compared to baseline—complement C3 (-24.9%), YKL40 (-22.9%), sTREM2 (-28.2%) and GFAp (-34.6%).
The role of neuroinflammation in PD has been increasingly explored over the past decade. It has been shown that abnormal processing of α-synuclein may reveal parts of the protein structure that are not normally exposed, causing the immune system to recognise this as a foreign protein. The unwanted activation of immune cells contributes to the dopaminergic loss of neurons in PD.
Some companies have been investigating this approach to target PD patients in early stages of the disease, such as Roche/Prothena’s monoclonal antibody, PRX-002, but there are currently no available treatments that offer neuroprotection or halt the disease progression. As such, the advancement of ANVS401 into Phase III trials is a vital step toward providing further evidence to back up this hypothesis. The company is planning to initiate two Phase III studies by the third quarter of this year in the US in PD and AD, after presenting the final results of the Phase II trial.
Key opinion leaders (KOLs) interviewed by GlobalData expressed that the α-synuclein pathway has been gaining increasing recognition among the PD research. α-synuclein is mainly tested in cerebral spinal fluid (CSF), however, which adds a major difficulty in the process of collecting these samples during clinical trials. As well as this, it remains challenging in clinical trials to differentiate between the symptomatic effects of drugs that target this approach and the potential neuroprotective properties. This is due to the difficulty to assess neuroprotective benefits in the absence of reliable biomarkers and the need to target patients earlier in the course of disease progression.
Further research is indeed needed to develop new therapies for the future PD market, given that the current options only offer symptomatic relief at moderate efficacy alongside their associated side effects and complications.