Biotech entrepreneurs ask themselves the same question software entrepreneurs ask.
"Do we want to build a platform or a product?"
Traditionally, entrepreneurs, both software and biotech, have focused on building single-product companies. In biotech, that means a specific drug, and in software it means providing a specific tool or service.
Now, platform startups are the rage, especially in silicon valley. 'Come for the tool, stay for the platform' has become the mantra for many early stage entrepreneurs.
In biotech, a platform essentially means providing centralized set of technologies and services to support the drug development process. This includes lab diagnostics, therapeutic protocols, antibodies, or testing devices. While product (drug) focused companies spend years (and tons of $$$) in research and clinical trials before making any money, platform companies see cash flow much earlier in their life cycle by licensing their platform to these drug manufacturers.
It is interesting that these biotech platforms look very similar, not to tech platforms like Twitch or Twitter, but more like the recent wave of VC platforms.
VC firms have started developing their internal platforms to provide additional support to their portfolio companies in addition to capital. This includes full-stack access to tools, resources, and personnel. It is a great way to create a competitive advantage and build a closer relationship with their founders while simultaneously building a village of competence around them. Similarly, these biotech platform companies get a chance to support the development of several different drugs simultaneously, build relationships with big pharmaceutical companies, and provide them (relatively) inexpensive drug development services.