Kamala Films has acquired rights to the Lone Wolf and Cub manga, which is now in active development again according to Deadline.  Kamala will produce with 1212 Entertainment, and there are some major league attachments.  David and Janet Peoples (Blade Runner, Unforgiven, and Twelve Monkeys) are writing a script; and Justin Lin (Fast Five) is attached to direct. 
Darren Aronofsky was attached to direct a Lone Wolf and Cub feature almost ten years ago (see "Pi Helmer Gets 'Lone Wolf'"); perhaps this time around a film, set in the Edo period in Japan, can get made.  Dark Horse Comics publishes the manga series here in the U.S.