The reverse ADS split by NuCana plc is a strategic move to improve stock liquidity and meet Nasdaq's listing requirements. While the company aims for a proportional increase in the trading price post-split, there's no guarantee of this outcome. However, such corporate actions typically aim to make the stock more appealing to investors by adjusting the share price to a more attractive level. The immediate effect on the stock price is uncertain, but the intent is to positively influence investor perception and stock market performance.