An estimated 90% of the global population is infected with Epstein-Barr virus (EBV). In some cases, this infection is asymptomatic; in others, EBV can lead to numerous health impacts, including the development of certain cancers. Research suggests that EBV is associated with 2% of cancers on a global scale, including lymphoma, gastric cancer, and nasopharyngeal carcinoma.
In December 2023, Viracta Therapeutics, Inc. (“Viracta”) shared that the U.S. FDA granted Orphan Drug designation to Nana-val (nanatinostat in combination with valganciclovir) for nasopharyngeal carcinoma. This is not the first Orphan Drug designation granted to Nana-val in the U.S., but the fifth. That being said, this is the first time the designation has been granted for EBV+ solid tumors.
Nana-val is an orally administered investigational combination therapy that combines HDAC inhibition with antiviral properties. It is being explored in various clinical studies for use in varied indications.
What is Orphan Drug Designation?
Granted by the U.S. Food and Drug Administration, Orphan Drug designation is a status given to drugs or biologics that intend to either treat, diagnose, or prevent rare conditions. The definition of “rare” varies worldwide; in the U.S. rare refers to conditions which affect fewer than 200,000 people nationwide. This designation comes with benefits and incentives for drug developers to ensure that adequate attention is given to the rare disease drug development process. Viracta will receive tax credits, fee waivers, protocol assistance, and even seven years of market exclusivity if/when the drug is approved.
Currently, available treatments for nasopharyngeal carcinoma include surgery, radiation, and chemotherapy. Nana-val could transform the treatment landscape by offering a less invasive and more targeted therapeutic option.
The Orphan Drug designation was also given based on positive interim data from a Phase 1b/2 clinical study which is exploring the treatment as a monotherapy and in conjunction with pembrolizumab. Participants in the study have EBV+ nasopharyngeal carcinoma that either recurred after treatment or has spread elsewhere. In the first portion of the study, researchers are examining how safe the treatment is and what dose should be used in further studies. Next, in Phase 2, researchers will evaluate how safe and well-tolerated Nana-val is, what antitumor properties it has, and its pharmacodynamics and pharmacokinetics.
What to Know: Nasopharyngeal Carcinoma (NPC)
Your nasopharynx is located behind your nose and at the back of the throat. When cancer forms in this area, it’s known as nasopharyngeal carcinoma. While this cancer is more common in Southeast Asia, it is considered rare within the United States. Doctors don’t know exactly what causes this cancer, but they have identified risk factors. If you are male, EBV+, between the ages of 30-50, have a family history of NPC, are exposed to salt-cured food in childhood, or are of northern African, Chinese, or Southeastern Asian descent, your risk of developing nasopharyngeal carcinoma is higher.
Nasopharyngeal carcinoma can be difficult to detect in early stages; some individuals remain asymptomatic, and others have symptoms that mimic more common conditions. When symptoms do occur, these can include:
- Hearing loss (often on one side)
- Tinnitus (ringing in the ears)
- A lump in the neck that doesn’t go away after a few weeks
- Headaches
- Swollen lymph nodes
- Nasal congestion (often on one side)
- Bloody saliva and/or bloody discharge from the nose
- Double vision
- Frequent ear infections
- Sore throat
- Difficulty swallowing
- Hoarseness
