Should you reconsider your ‘go-to’ chemical probe?
Do you have a tendency to go back to the chemical probe you know will work for you, or that has been on the market for a long time? Well, our data suggests that you aren’t alone, but you might find that trying some newer options might give you better results.
Many of the newer chemical probes that are available today target the same protein as popular older versions, but have better properties, such as higher selectivity and potency. However, in this market it can take quite a bit of time before newer products are really taken up and used.
CiteAb product manager Rebecca Sadler has been looking at our citation data for chemical probes to better understand how citation shares change over time for newer and older products.
She says: “I took PI3K inhibitors as a test case and looked at citations comparing chemical probes that target PI3 kinase, LY294002, GDC-0941 (Pictilisib) and BYL-719 (Alpelisib).
“I chose PI3 kinase inhibitors because LY294002 is in the top ten most cited chemical probes, but newer probes with the same target but higher selectivity and potency have been released within the past ten years.”
LY294002 is the oldest compound that Rebecca looked at – the first citation for it in our database appeared in 1998. The first citation for GDC-0941 is later in 2011, and for BYL-719 is in 2015.
Rebecca explains that “the first citation may not equivalent to the ‘release date’ of product as it may have taken a while for commercial companies to start selling new products especially if there are patents protecting the molecules – in fact it looks like GDC-0941 was discovered in 2008, and BYL-719 in 2013.”
Our data suggests that LY294002 actually maintained 100% of the share of citations across the three chemical probes from 1998 until 2011 when the first citations from GDC-941 started to appear. By 2015 citations from BYL-719 also began to take some share from LY294002.
Rebecca says: “What is clear from this data is that it took a few years after new versions were discovered for us to start seeing citations, and even then the move of citation share from LY294002 to new products was very gradual – between 2010 to 2017 citation share for LY294002 gradually decreased from 100% to 93.33%, still quite high given more targeted products were available.”
So why are new probes so slow to increase their market share? Rebecca tells us that this could be due to the number of suppliers providing each product – for example LY294002 has citations from nine different suppliers, while GDC-0941 only has citations from two suppliers, and BYL-719 from one.
Looking to try a newer PI3 kinase inhibitor?
GDC-0941 suppliers on CiteAb are Abcam, Abmole, AdooQ, Cayman, MedChem Express and Selleck Chemicals.
BYL-719 suppliers on CiteAb are AdooQ, Cayman, MedChem Express and Selleck Chemicals.
Would you like to see the percentage market share between 2010 and 2017 for each of the three named chemical probes from this blog for free? Sign up below and we’ll send the data to your inbox.
Sign up for data
Something seems to have gone wrong while loading the form.
Drop us a message and we can send you the data directly.
Useful links:
- GDC-0941 was first discovered in 2008, see this paper: https://www.ncbi.nlm.nih.gov/pubmed/18754654
- BYL-719 was first discovered in 2013, see this paper: https://www.ncbi.nlm.nih.gov/pubmed/23726034
- The discovery of LY294002 is outlined in this paper: https://www.ncbi.nlm.nih.gov/pubmed/8106507
- For a good summary of PI3kinase inhibitors and their relevance in clinical research, especially in looking for cancer treatments, see http://ar.iiarjournals.org/content/32/7/2463.long. Note that only GDC is mentioned, and the paper also looks at other similar inhibitors that aren’t PI3K specific.
- Another paper for reference is from AACR, mentioning GDC and BYL among other inhibitors and looking at relevance for cancer research/treatment. This paper goes into a lot more detail looking at different inhibitors than previous paper http://mct.aacrjournals.org/content/13/5/1021
– Alicia and the CiteAb team