I found something that could answer how Zenpep is different... the various enzyme versions differ in the levels of the various components they contain. Zenpep has it's own 'proprietary' formula, as stated in this article from 2008 while it was still in development:
an excerpt from: <a target=_blank class=ftalternatingbarlinklarge href="http://www.medicalnewstoday.com/articles/137332.php">Innovatively Formulated Pancreatic Enzyme Product - FDA Accepts Response To Approvable Letter For EUR-1008 As Complete</a>
<div class="FTQUOTE"><begin quote><b>About EUR-1008 (ZENTASE(R))</b>
Eurand's lead product candidate, EUR-1008 (ZENTASE(R)), is an innovatively formulated pancreatic enzyme product that is being developed for the treatment of exocrine pancreatic insufficiency, a condition associated with cystic fibrosis, chronic pancreatitis and other diseases. The product was developed in response to the 2006 FDA guidance on pancreatic enzyme products, which outlined the need to reduce the variability in enzyme levels and stability of currently marketed enzyme therapies and regulate them under NDAs. EUR-1008 is a highly stable formulation of a porcine pancreatic extract that includes eight key enzymes and a number of coenzymes and cofactors and is biologically similar to the endogenous human pancreatic secretions necessary for proper human digestion. The Company plans to market EUR-1008 in the U.S. and out-license the product outside the U.S.</end quote></div>
(Zentase was the originally proposed name; it was changed to Zenpep.)
an excerpt from: <a target=_blank class=ftalternatingbarlinklarge href="http://www.medicalnewstoday.com/articles/137332.php">Innovatively Formulated Pancreatic Enzyme Product - FDA Accepts Response To Approvable Letter For EUR-1008 As Complete</a>
<div class="FTQUOTE"><begin quote><b>About EUR-1008 (ZENTASE(R))</b>
Eurand's lead product candidate, EUR-1008 (ZENTASE(R)), is an innovatively formulated pancreatic enzyme product that is being developed for the treatment of exocrine pancreatic insufficiency, a condition associated with cystic fibrosis, chronic pancreatitis and other diseases. The product was developed in response to the 2006 FDA guidance on pancreatic enzyme products, which outlined the need to reduce the variability in enzyme levels and stability of currently marketed enzyme therapies and regulate them under NDAs. EUR-1008 is a highly stable formulation of a porcine pancreatic extract that includes eight key enzymes and a number of coenzymes and cofactors and is biologically similar to the endogenous human pancreatic secretions necessary for proper human digestion. The Company plans to market EUR-1008 in the U.S. and out-license the product outside the U.S.</end quote></div>
(Zentase was the originally proposed name; it was changed to Zenpep.)