One angle is the use of parasites to treat autoimmune diseases. It wasn't mentioned in the article, but hookworms are being studied for their ability to secrete a wide range of immune-modulating molecules. Companies are trying to determine which molecules are especially useful, and in what combination, so they can synthesize them and sell them.
But, you can get their beneficial effect right now, which is very appealing to people with major autoimmune diseases. Some companies are selling parasite eggs by mail to people who otherwise can't get them. I have MS, I take them.
It's not a lucrative business, and there are a lot of regulatory hurdles, but the treatment is quite safe.
Most people are disgusted by the idea of infecting their self with parasites. The reality is that humans evolved with parasites constantly inside of their bodies. It's only in the last 100 years that widespread anti-parasitic medication has wiped them out.
That did a lot of good for society in general, but we took it too far, essentially, by wiping out parasites entirely. There are a lot of benign "parasites", which should be thought of as symbiotes.
The way that big pharma is dealing with this is as mentioned above: they're trying to synthesize the right stew of immune-modulating chemicals to deal with this. But the immediate solution is to educate people, and sell them clean, safe parasites (or their eggs).
It's also nice if they live a long time in their host, and don't reproduce inside of the host. This is why Necator Americanus is mostly used; it fits all of these characteristics.