To my knowledge that study was never published because it was not done by the FDA as part of the new drug approval process. It was done by the Drug Enforcement Administration (DEA) with an orientation toward abuse potential rather than possible clinical use. As you may be aware, the DEA does not have a strong history of sharing information even with other governmental agencies. The DEA was worried that the prodrug was going to break apart leaving a water solution of amphetamine that could then be snorted or injected.
My understanding is that at the end of one year at room temperature there had been no degradation of the prodrug… none at all. If there had been some breaking of the lysine bond, the amphetamine base would have decomposed in water within a matter of days. That is why we went 30 years without a liquid formulation of an ADHD stimulant even though 30% of kids can’t swallow pills. The many liquid formulations that we now have on the market are colloidal suspensions and not water solutions. The MPH and AMPH are “hidden” from the water in ion exchange resins so that they will not decompose.
You may also notice in the PDR and package insert that the FDA says that it is OK to dissolve Vyvanse in water but that whatever portion that is not used immediately should be discarded. This last direction to discard the solution is not based on there being some reason not to keep it but rather that the FDA will only approve something that they have studied themselves. Since the FDA did not study stability in water, their answer was that you have to throw it away.
In my own practice I had well over 100 people who dissolved their Vyvanse in water and the solution retained it’s full efficacy for months. I did not have a single problem with it.
Dr. Bill Dodson