Talimogene laherparepvec (Specialist drug)

How it works

The attenuated virus replicates selectively within tumour cells, causing them to lyse, and it expresses GM-CSF to promote a local and systemic anti-tumour immune response.

Prescribing in practice

• Because it is a live attenuated herpes virus, it must not be given to severely immunocompromised patients, and healthcare staff and close contacts who are immunocompromised or pregnant should avoid contact with injection sites and dressings to prevent accidental transmission.
• Herpetic infection can occur in patients and theoretically in contacts; aciclovir or other antivirals can treat herpetic infection but may reduce the medicine's effectiveness.
• Administered by intralesional injection by trained specialists with standard precautions for handling and disposal.

Monitoring

Monitor injection sites and lesions for response and for signs of herpetic or other infection, including cellulitis.

Counselling the patient

• Keep injection sites covered as instructed and avoid touching or scratching them.
• Avoid close contact with people who are pregnant, infants, or those with weakened immune systems while sites are healing.
• Report cold-sore-like symptoms, fever, or spreading skin redness.

Evidence & guidelines

Approval was based on a randomised trial demonstrating improved durable response rate in advanced melanoma.