First of three movies Lon Chaney Jr and Lloyd Bridges appeared in together. The other two are 16 Fathoms Deep (1948) and High Noon (1952).
The influenza drug, branded as 'zymurgine' in the movie, is appropriately named: Zymurgy is the chemistry of fermentation with yeasts, and the Lon Chaney character is searching for a "South American mold" to ensure its effectiveness.
Due to a rights dispute (being an unauthorized remake of The Man Who Reclaimed His Head (1934)), this film was not released to television with the other "Inner Sanctum" features. It was the fifth of the six entries, filmed February 1-14, 1945, and released October 5. After its theatrical reissue using the title "The Missing Head", the film vanished until its video release in the 1990s.