I’ll try to answer your questions.
My other question is that according too what NIH says about Phase I trials is that the treatment doses were likely not to be therapeutic, but Ceregene Phase I did show clinical improvement with GFDNF delivery
--The NIH phase 1 trial will test 4 different doses of GDNF. The first group of patients will receive the lowest dose. If this proves safe, the 2nd group will receive a higher dose, and so on for groups 3 and 4
“Phase 1 single-center, open-label, dose escalation, safety and tolerability study of adeno-associated virus, serotype 2 vector (AAV2) containing human GDNF complementary DNA bilaterally delivered by convection-enhanced delivery (CED) to the putamen (450 (alpha) l per hemisphere) of 24 patients with advanced PD. An additional 4 subjects will be allowed for screening failures. Four escalating dose levels will be evaluated in the following dose cohorts (6 patients per cohort): Cohort 1 = 9 x 10(10)vg, Cohort 2 = 3 x 10(11)vg, Cohort 3 = 9 x 10(11)vg and Cohort 4 = 3 x 10(12)vg”
---In the Ceregene trials, another growth factor (neurterin) was used.
Did Amgen Phase I people show similar response?
--- Amgen sponsored the phase II trial which delivered the gdnf protein into the brain with an implanted infusion pump and catheter.
The phase I trials were conducted by the University of Kentucky and Frenchay Hospital, Bristol, United Kingdom. Both reported good results.They were both open label – all phase I participants received gdnf and knew it.
Amgen claimed the reason the phase I trials were successful was due to the placebo effect, anfd that the phase II did not meet its endpoints. Many of the trial participants challenged this. You can read about them in the book Monkeys in the middle.
For more on these studies see
At the first World Parkinson’s Congress , I met one of the phase II participants. I could not tell that he had PD. After talking to him, I became a true believer in the potential of gdnf.
The current NIH trial will use gene therapy to deliver the gdnf gene, instead of a pump, although a new pump delivery method is being tested in the UK
Does successful completion of the first trial secure you a spot in the next trial? I hate to sound selfish but have to weight trials in terms of my window of benefit from DBS.
You can only be in one trial. The phase I – all participants will receive GDNF. If it goes on to a phase II, based on curre nt practice , it is likely some will receive the treatment, and the others will receive sham surgery.