He doesn't seem to have a Wikipedia page or anything. What happened to him? I'm guessing he's dead now. When did he die? Any heirs or relatives?
Here you can see how Leandro Panizzon and his wife Marguerite looked in their old age.
After, as was usual at that time, testing his invention himself with no apparent result, he let his wife have a try (who suffered from low blood pressure). Methylphenidate apparently improved her tennis capabilities. Today it is used not only as medicine, in cases of ADHS (which seems to be a fabricated illness), but also as a drug (called Rita).
In 1950 Panizzon together with Max Hartmann obtained a US patent (number 2507631) for an improved manufacturing method of methylphenidate. In 1954 methylphenidate came on the market. In 2014 Novartis had a turnover of 492 million US-Dollar with Ritalin. In 2013 338 kg Ritalin were sold compared to 23 kg in 1998.
Panizzon got vice-director of his Swiss company Ciba (today Novartis)
He died in 2003.
The couple had four children.