Medications and treatment devices are emerging to control and improve the symptoms of patients with Parkinson's disease.
On April 4th (local time), the U.S. Food and Drug Administration (FDA) approved Onapgo, a treatment device for motor fluctuation symptoms developed by Supernus Pharmaceuticals. This follows the approval last October of Vyalev, a Parkinson's disease treatment from AbbVie that also received FDA approval.
Parkinson's disease is characterized by a lack of dopamine in the brain that controls muscle movement, leading to stiff muscles. It is the second most common degenerative brain disease after dementia. Most patients exhibit motor fluctuation symptoms, such as trembling hands and feet (tremors), slowing of movements (bradykinesia), rigidity (stiffness), and unstable gait (gait disturbance).
Until now, the only treatment for improving motor fluctuation symptoms was AbbVie's Vyalev. This subcutaneous (SC) infusion pump combines levodopa, a precursor to dopamine, with carbidopa to reduce side effects. It was developed to deliver continuous treatment like an insulin pump to alleviate motor symptoms in patients with advanced Parkinson's disease.
The recently approved Onapgo also aims to treat motor fluctuation symptoms in adult patients with advanced Parkinson's disease, but it is the first wearable apomorphine subcutaneous infusion device.
According to Supernus, while existing injectable medications require manual injections every two hours, Onapgo automatically infuses apomorphine, a dopamine agonist, subcutaneously when worn, thereby improving motor fluctuation symptoms. The company plans to launch Onapgo in the U.S. market in the second quarter of this year.
Both treatments are administered continuously over 24 hours, preventing the symptoms from recurring or worsening due to diminished efficacy. The results of clinical trial phase 3 for Onapgo indicated it reduces the time until the drug's effectiveness decreases by about 2.6 hours compared to existing therapies. In this regard, U.S. securities company Jefferies evaluated that Onapgo exhibits fewer skin nodules and injection site reactions, indicating better tolerability than Vyalev.
As such, alongside developing treatments that enhance dopamine levels to alleviate motor symptoms, there is also a continued effort to develop more fundamental therapies that can prevent the onset and progression of Parkinson's disease. First, AbbVie is currently awaiting FDA approval for tavapadon, an oral medicine that promotes dopamine secretion. There are five types of dopamine receptors, from D1 to D5, and tavapadon partially binds to the D1 and D5 dopamine receptors, which play a role in regulating motor activity.
Domestic corporations are also accelerating the development of new drugs for Parkinson's disease. MediHelpLine is conducting domestic phase 3 clinical trials for its candidate substance WIN-1001X. WIN-1001X protects brain nerve cells, normalizes dopamine secretion, and prevents the death of nerve cells. It was selected in 2018 for the Advanced Medical Technology Development Project by the Ministry of Health and Welfare. Kainos Medicine is also conducting phase 2 clinical trials for the candidate substance KM-819 in the U.S.
S.Biomedics is conducting phase 1 and 2a trials on 12 domestic Parkinson's disease patients, using embryonic stem cells, the first of its kind in Asia. HL192, a Parkinson's disease treatment being co-developed by Daewoong Pharmaceutical and HANALL BIOPHARMA with U.S.-based Neuron Pharmaceuticals, has completed phase 1 trials and is nearing phase 2.
ABL Bio's Parkinson's disease treatment ABL301, transferred to Sanofi in 2022, is currently in phase 1 trials. A notable feature is the use of the Grabbody-B platform for brain blood barrier (BBB) penetration. Aprogen recently started developing Parkinson's disease treatments after acquiring Aptenuroscience, working alongside Jeong Jong-kyung, the head of the Genetic Engineering Research Institute at Seoul National University, to create a new material that prevents the death of dopamine neurons.
In contrast, Peptron, D&D Pharmatech, and Bukwang Pharmaceutical have failed to demonstrate efficacy in phase 2 trials. Bukwang Pharmaceutical has not met its primary endpoint but plans to reinforce clinical data through subgroup analyses before considering technology transfer.