CRISPR, VRTX stock prices waver as US FDA approves Casgevy

The Crispr Therapeutics (NASDAQ: CRSP) stock price moved sideways after the Food and Drug Administration (FDA) approved Casgevy. The shares were trading at $70.30 on Friday, where they have been in the past few days. They are 84% above their lowest level in November.

Crispr Therapeutics and Vertex Pharmaceuticals received good news after the FDA approved the first gene editing treatment for sickle cell patients. This is a major event since it is the first time that such a treatment has been approved in the US. It came a few weeks after the UK approved it. 

Casgevy was developed by scientists at the two companies to treat sickle cell, a disorder that affects hundreds of thousands of people around the world. The disease causes red blood cells to misshapen half moons that get stuck inside blood vessels. As a result, it restricts blood flow and can cause pain crises. In a statement, Nicole Verdum of the FDA said:

The process of treating sickle cell using this process is not easy. In the first step, patients will need to have a blood sample that will be sent to Vertex, where they will be genetically modified. After this, the drug will be administered to the patients for a few days and spend weeks in hospitals recuperating. Vertex hopes to target over 32k people in the US and Europe.

Therefore, Crispr stock price reacted mildly to the announcement because it was largely expected. This explains why the shares have jumped by more than 80% in the past few weeks. This situation is known as buying the rumour and selling the news.It also explains why the  Vertex Pharmaceuticals (VRTX) stock price also retreated to $350 after the news.