If you could take a vaccine to prevent disease progression, would you? Well, researchers recently tested the efficacy of such a vaccine for patients with Parkinson’s disease. The experimental and investigational vaccine, called Affitope PD01A, is developed by Affiris. After positive Phase 1 trial results, published in The Lancet Neurology, the vaccine will be further studied in a Phase II trial starting in late 2020 or early 2021.
Parkinson’s disease is a progressive central nervous system (CNS) disorder which causes issues with movement and motor function. It occurs in five stages, ranging from the first (light tremors) to the most severe stage, in which patients cannot walk, stand, or live on their own. Generally, Parkinson’s disease onset occurs after 50 years old. Symptoms include:
- Muscle stiffness and rigidity
- Poor balance and posture
- Slowed movement
- Inability to blink or smile
- Changes in speech
- Hallucinations or dementia
Learn more about Parkinson’s disease.
What is the vaccine?
Affitope PD01A is an investigational vaccine which targets alpha-synuclein, a protein found in brain cells. In patients with Parkinson’s disease, alpha-synuclein builds up into toxic clumps called Lewy bodies. These not only damage brain cells, but prompt cell death.
Thus, Affitope PD01A works to stimulate the immune system and create antibodies against alpha-synuclein. As a result, the vaccine could reduce levels of Lewy bodies or prevent them from accumulating, halting disease progression.
In fact, these results were first seen in preclinical studies. When treated with Affitope PD01A, mice models of Parkinson’s disease experienced better memory, better motor function, and lower levels of Lewy bodies.
Phase I Trial for Affitope PD01A
During the first Phase 1 trial, 24 participants with early-stage Parkinson’s disease between the ages of 45 and 65 were given 4 subcutaneous injections at either 15 or 75 mcg. These 4 injections were given once every 4 weeks for a 1-year period. 3 patients withdrew from the study.
Next, participants entered into an extension study and monitored for 1 year, then again for 10 months. Then they were divided again into 2 groups, during which time they received a booster vaccine and studied for 6 months. After 6 months, they received a 2nd booster shot (75 mcg) and monitored for an additional 1 year period. Ultimately, 21 patients received all 6 shots.
Researchers discovered that:
- Affitope PD01A increased alpha-synuclein-targeting antibodies.
- For those receiving 75 mcg injections, alpha-synuclein levels dropped by 51%.
- Antibody levels began falling after 2 years, but rose with booster shots.
- Affitope PD01A was safe, effective, and well-tolerated, even when taken long-term.
- Side effects included fatigue, muscle pain and rigidity, tremors, and headaches.
Read the source article here.