I heard about this research a while back so I assume it has now progressed. I like articles where they look to nature to find all these fascinating medical applications. I think of the first migraine abortive ergotamines made from Ergot which is a poison and in some theories was blamed for the Salem witch trials.(WebMd). To think you can take that and abort a migraine is amazing. From that they invented the triptan itself. So a lot can come from researching what nature has to offer.
In Australia at the university of Queensland, researchers have looked at the venom of over 200 spider species. The researchers have found a specific toxin in the venom of the tarantula (specifically Thrixopelma pruriens or Peruvian Green Velvet Tarantula) that shows potential as a painkiller. One that's not addictive (of course) and more effective that opioids (since those are not actually that effective for pain). The Peruvian Green Velvet Tarantula's venom inhibits pain receptors. Specifically, "the peptide toxin the researchers refer to as ProTx-II inhibits pain signals by binding to the membranes of nerve cells." Pain News
"Our results show that the cell membrane plays an important role in the ability of ProTx-II to inhibit the pain receptor. In particular, the neuronal cell membranes attract the peptide to the neurons, increase its concentration close to the pain receptors, and lock the peptide in the right orientation to maximize its interaction with the target," said Henriques, who presented her latest findings at the annual meeting of the Biophysical Society in Los Angeles Pain News
Of the 200 spiders they have researched 40% contain one compound that blocked Nav 1.7 channels. They have over 45k spiders to explore. "Our work creates an opportunity to explore the importance of the cell membrane in the activity of peptide toxins that target other voltage-gated ion channels involved in important disorders," said Henriques.Pain News
Pain News Network says there has been research into the venom of cone snails as well. I remember reading those too. Similarly it also blocks pain signals. One advantage stated was that it decomposed quickly and therefore unlikely to cause dependency. One drug called Prialt is in this category; it is injected into the spinal cord and treats severe pain of a failed back surgery, injury, AIDS and cancer.
Interesting research on the horizon...