Has biotech produced any medicine for age-related loss of memory and cognitive decline?

Yes. There are several drugs on the market which show measurable effects on the slowing of cognitive decline with alzheimer's. These are the cholinesterase inhibitors (aricept, exelon, (rivastigmine) razadyne) and they are used in combination with namenda. They are not fda approved for age-related cognitive impairment, but help increase the activity of acetylcholine, which may be deficient in some patients with arci.