This is marketing research on the RSV research industry and can include information on the background, market structure, definitions, competitors, trends and developments of RSV research and is related to other topics such as drugs and healthcare.

RSV: lack of vaccine puts most vulnerable at risk

An infection with the respiratory syncytial virus can result in hospitalization and sometimes respiratory failure. With no suitable treatment available and the only preventative medication considered too expensive to be widely prescribed, the need for an effective vaccine is high. However, given the failure of recent developmental efforts the launch of a successful vaccine is still some time away.

An infection by the respiratory syncytial virus (RSV) usually causes upper respiratory tract infections (URTIs), resulting in symptoms of the common cold. However, in certain risk groups, RSV can also cause lower respiratory tract infections (LRTIs). When RSV causes severe LRTIs, these usually manifest as bronchiolitis or pneumonia, which can lead to respiratory failure. The most important risk factors include prematurity, underlying cardiac or pulmonary disease, compromised immune system and old age. Other risk factors are related to the environment of the patient, such as crowded living conditions and exposure to tobacco smoke.

A total of 18 million people annually become infected by RSV in the seven major markets (US, Japan, France, Germany, Italy, Spain, UK), including three million adults with underlying disease and almost 400,000 premature infants. Approximately 900,000 of the individuals in these risk groups are hospitalized for this infection each year. Although mortality is low, the high number of hospitalizations makes RSV a costly disease.

Treatment options limited

The RSV market is currently dominated by MedImmune's prophylaxis Synagis (palivizumab), a recombinant human monoclonal antibody. Synagis was launched in 1998 and now has sales of around $750 million per RSV (winter) season. Although Synagis is quite effective in preventing RSV hospitalizations, its cripplingly high costs mean that its use is limited to the most vulnerable risk groups: premature infants and children with chronic lung disease or congenital heart disease.

In addition to this prophylaxis, Valeant Pharmaceuticals' Virazole is the only treatment on the market for RSV. However, this drug has fallen out of favor because of its limited efficacy and only reached sales of $2.5 million in the most recent RSV season. An effective vaccine to prevent RSV in the most vulnerable population groups is essential, rather than using drugs with little efficacy.

Road to successful RSV vaccine full of hurdles

Despite the high need for an RSV vaccine, many large vaccine companies have abandoned their developing efforts. The main reason is thought to be financial, although disease specific difficulties also play a role. The two major patient groups - elderly and infants - dwell at the opposite ends of the age spectrum, each presenting their own problems. Furthermore, the moral and ethical dilemma of testing new drugs on premature babies is very difficult to resolve for both parents and clinicians. Finally, the respiratory syncytial virus itself has several characteristics that makes the development of vaccinations difficult.

Again, it is MedImmune that dominates the limited RSV vaccine development; with MEDI-534 the most advanced RSV vaccine in the pipeline. Nevertheless, this drug is currently in phase I clinical development, which means that a vaccine for RSV is still a long way from being ready to be prescribed.

Diagnosis difficulty

The peak incidence of RSV infections occurs in the winter months, usually coinciding with the influenza epidemic. Since symptoms of influenza and RSV are similar, it is difficult to make a correct diagnosis without specific tests. A rapid diagnosis of RSV in people admitted to hospital can help prevent nosocomial transmission, since patients can be either assigned to private rooms or cohorted with other RSV infected patients. Additionally, a faster negative RSV diagnosis may offer the patient a chance of a more rapid treatment of, for example, bacterial infections or influenza. Nevertheless, since there is currently no specific treatment for RSV infections, physicians do not always value diagnosis as important.

Viral cultures are considered the gold standard method of RSV diagnosis. However, specific confirmation generally requires several days, presenting a dilemma for patients who may require immediate treatment. Antigen detection assays have become a common rapid method of detection, although all of these tests lack sensitivity, making them only appropriate during epidemics, when high volumes of tests need to be performed in a short time span.

While RSV is a common virus causing only cold-like symptoms in healthy individuals, it can be very dangerous for the more vulnerable people of society. The high costs of available prophylaxis combined with under-diagnosis and a lack of effective treatment mean that more people suffer serious complications from an infection with this virus than necessary. A vaccine would mean a big step forward in the prevention of hospitalizations and maybe even deaths, however, it will take some time before a vaccine reaches the people who need it most.

Related research:

• Stakeholder Opinions: Respiratory Syncytial Virus (RSV) - A market yet to reach its full potential

• Stakeholder Insight: Respiratory Tract Infections in the USA - The demise of narrow-spectrum antibiotics

• Commercial Insight: Herpes and Respiratory Antivirals - Leaders Rise and Fall