Why In News?

VERVE-102 is an experimental, one-time in vivo base-editing gene therapy designed to permanently switch off the PCSK9 gene in the liver, durably lowering disease-driving bad (LDL) cholesterol.

What is VERVE-102?

  • VERVE-102 is an experimental gene-editing medicine designed to permanently switch off PCSK9 in liver cells, reducing LDL-C over the long term.

  • In-vivo Editing: Unlike ex-vivo therapy, the editing machinery is delivered directly into the patient's body, where it edits target cells.

  • Base Editing: It uses an adenine base editor (ABE) to make a targeted DNA base change without creating the conventional double-strand DNA break associated with many CRISPR approaches.

  • Target: PCSK9 regulates LDL-receptor availability in the liver; reducing PCSK9 helps the liver remove more LDL-C from blood.

  • Delivery: VERVE-102 uses a GalNAc-LNP system and is administered through an intravenous infusion targeting liver cells.).

  • Single Course: The objective is to replace repeated cholesterol-lowering treatment with one durable genetic intervention, although long-term durability is still being established.

What is Base Editing?

  • Base editing directly changes one DNA base into another without necessarily cutting both DNA strands.

  • Genetic Precision: VERVE-102 uses an adenine base editor designed to create a specific A-to-G change at the PCSK9 target site.

  • CRISPR Difference: Traditional CRISPR-Cas9 generally creates a DNA double-strand break, while base editors chemically modify individual bases.

  • Advantage: Avoiding a double-strand break may reduce some unwanted DNA damage associated with conventional nuclease-based editing.

  • Limitation: Base editors can still produce off-target edits and unintended molecular changes, requiring extensive safety testing.

How Does VERVE-102 Work?

  • Step 1: An intravenous infusion introduces VERVE-102 into the bloodstream.

  • Step 2: Its GalNAc-LNP delivery system facilitates uptake into liver cells.

  • Step 3: The LNP releases base-editor mRNA and guide RNA inside the cells.

  • Step 4: Cells translate the mRNA into the adenine base-editing protein.

  • Step 5: The guide RNA directs the editor towards the PCSK9 DNA sequence.

  • Step 6: The editor makes a targeted A-to-G DNA change designed to permanently inactivate PCSK9.

  • Step 7: Reduced PCSK9 activity allows more LDL receptors to remain available on liver cells.

  • Result: Greater LDL clearance from blood can produce a long-lasting reduction in LDL-C.

 

What is PCSK9?

  • PCSK9 is a protein involved in controlling the number of LDL receptors on liver cells.

  • Normal Function: PCSK9 promotes degradation of LDL receptors, reducing the liver's ability to remove LDL-C.

  • Gene Inactivation: Lowering PCSK9 increases LDL-receptor availability and therefore enhances LDL-C clearance.

  • Therapeutic Logic: Human genetics provides strong evidence that naturally lower PCSK9 activity is associated with lower cardiovascular risk, supporting PCSK9 as a drug target.

What is LDL Cholesterol?

  • LDL-C: Low-density lipoprotein cholesterol transports cholesterol through the bloodstream and is commonly called “bad cholesterol.”

  • Plaque Formation: Persistently elevated LDL-C contributes to cholesterol deposition in arterial walls.

  • Atherosclerosis: Long-term LDL exposure promotes atherosclerotic plaque formation, narrowing arteries and increasing cardiovascular risk.

  • Clinical Link: High LDL-C is an important modifiable risk factor for heart attack and stroke.

Source: INDIANEXPRESS

PRACTICE QUESTION

Q. With reference to VERVE-102, consider the following statements:

  1. It targets the PCSK9 gene.

  2. It uses an in-vivo base-editing approach.

  3. It is currently an approved treatment for familial hypercholesterolemia.

  4. It is delivered using a liver-directed GalNAc-LNP system.

Which of the statements given above are correct?

A. 1 and 2 only

B. 1, 2 and 4 only

C. 2 and 3 only

D. 1, 2, 3 and 4

Answer: B

Explanation:

Statement 1 is correct: VERVE-102 targets the PCSK9 gene in the liver to permanently lower LDL cholesterol.  

Statement 2 is correct: It uses an in-vivo base-editing approach (specifically an adenine base editor) to modify the DNA sequence. 

Statement 3 is incorrect: VERVE-102 is currently an investigational medicine in clinical trials (e.g., Phase 1b Heart-2 trial) and is not an approved treatment for routine use.  

Statement 4 is correct: It is delivered using a proprietary liver-directed GalNAc-LNP (lipid nanoparticle) delivery system, which targets the asialoglycoprotein receptor (ASGPR) on liver cells.