By Stephen Nakrosis 



  Altria Client Services on Tuesday said the U.S. Food and Drug Administration will begin a substantive review of the premarket tobacco product applications for 35 on! products made by Helix Innovations LLC, an Altria joint venture. 


  The on! line consists of a number of nicotine pouch products. 


  Altria said that in support of these applications it submitted over 66,000 pages of documentation, including six primary studies. 


  Write to Stephen Nakrosis at stephen.nakrosis@wsj.com