Help required- someone who is very knowledgeable of Veeva APIs.  This is probably not a large project, maybe just a couple of hours, but could lead to more.  Here is the description of the business problem:

we’ve been creating some forms for quick creation of Veeva objects, and that’s working fine… but I’m looking for a reliable way to have the user log in to Veeva through our SSO (Microsoft) prior to submitting data to the API.  Currently I’m popping up an Internet Explorer window, but it’s not bulletproof.  I could really use some suggestions at how best to approach that aspect.