Nielsen BioSciences’ SPHERUSOL Provides Physicians with New Test for Valley Fever

Nielsen BioSciences announced today the launch of SPHERUSOL® (Coccidioides immitis Spherule-Derived Skin Test Antigen), a skin test that provides valuable data to physicians managing Valley Fever infections. SPHERUSOL has been approved by the U.S. Food and Drug Administration as the only skin test to detect an immune response to the fungus called Coccidioides, or “cocci,” in patients with history of the disease. Valley Fever is a serious infection that usually affects the lungs and is caused by inhaling airborne spores of the cocci fungus, which grows in dry desert soil of the western United States from Washington to Texas, with the bulk of cases occurring in Arizona and California. Until now, tests available to physicians for Valley Fever have been limited to blood tests, X-rays, cultures and biopsies, none of which provide information about the cellular immune response, which is comprised of disease-fighting cells responsible for overcoming the disease.

“SPHERUSOL fills critical gaps in the current testing of Valley Fever,” explained Tom Carpenter,  DVM, Ph.D., senior vice president and chief development officer of Nielsen BioSciences. “With SPHERUSOL now broadly available, physicians have access to an important new tool to further inform their treatment decisions and incorporate into their standard of care of patients with this fungal disease.” Of the estimated 150,000 people per year who become infected1 with the Valley Fever fungus, 40 percent will develop symptoms, including fever, cough, chest pain, headaches, night sweats, or rashes(2). Diagnosis is often delayed for months as symptoms can be confused with the flu or bacterial pneumonia. The average patient misses a month of work or school. In severe cases, the fungal infection spreads from the lungs to other parts of the body, such as the central nervous system (brain and spinal cord infection), skin, bones and joints, can have life-long consequences and be life-threatening3.

“The information SPHERUSOL provides is important for tracking patients’ active infections and is critical to determining the urgency of care required for each individual. Knowing a patient’s skin test status helps me in managing my patients with Valley Fever,” said pulmonologist and author Craig Rundbaken, D.O., F.A.C.O.I., F.C.C.P., founder of the Arizona Institute of Respiratory Medicine and Valley Fever Clinic, in Sun City West, AZ.

Introduction of a new test for Valley Fever was also noted by U.S. House Majority Leader Kevin McCarthy (R-CA) and U.S. House Representative David Schweikert (R-AZ), who serve as the co-chairs of the bipartisan Congressional Valley Fever Task Force and are from the two states where the disease is most prevalent.

“As new advancements are made, the fight against Valley Fever continues to move forward. We must continue to work to improve the way we treat and prevent this disease,” said Majority Leader McCarthy.

“Valley Fever has silently affected entire communities in the southwest, including our families, friends, and even our beloved pets,” said U.S. House of Representative David Schweikert. “I am honored to be working with both our local businesses and constituency to help expand our efforts.  I see new developments, such as the introduction of the Spherusol skin test, as vital steps forward in the fight against Valley Fever.”

While Valley Fever is viewed as a regional disease of the desert west, the impact on the lives and economies of the region is substantial. Nationally in 2013 as many people were reported diagnosed with Valley Fever as were with the better-known disease tuberculosis.(4)



SPHERUSOL is a skin test antigen indicated for the detection of delayed-type hypersensitivity to Coccidioides in individuals with a history of pulmonary coccidioidomycosis.

Until now, clinicians had no commercially available test to see if the patient’s cellular immune system is responding to the disease. Spherusol addresses this unmet need because it is specifically designed to test the response of these disease-fighting cells to Valley Fever.

The safety and effectiveness of SPHERUSOL have not been established in pregnant and nursing women, the pediatric population, or individuals > 65 years of age. The use of SPHERUSOL to detect delayed-type hypersensitivity response in a general population with unknown exposure to Coccidioides has not been evaluated. Persons with acute or disseminated coccidioidomycosis may not develop a delayed-type hypersensitivity response to SPHERUSOL. Persons with immunodeficiency and a history of coccidioidomycosis may not develop a delayed-type hypersensitivity response to


Boxed Warning

The expected response to SPHERUSOL is a local area of inflammation at the site of the skin test. The reaction is usually dime to quarter size reaching maximum diameter between 24 and 48 hours. Larger accelerated reactions can occur, which may require treatment with local cold compresses and anti- inflammatory medication.
Systemic reactions can occur with skin test antigens and in certain individuals these reactions may be life-threatening or cause death. Emergency measures and personnel trained in their use should be immediately available. Patients should be observed for at least 20 minutes following the administration of a skin test. SPHERUSOL should never be given intravenously.


Additional Safety Information

The most common side effects in clinical studies were itching, swelling, pain and ulceration at the site. Certain drugs that suppress the immune system, such as corticosteroids, can prevent a delayed-type hypersensitivity response to SPHERUSOL.

See www.nielsenbiosciences.comfor Full Prescribing Information.


About Nielsen BioSciences

Nielsen BioSciences is a privately held biotechnology company based in San Diego and founded in 2013. The company focuses on developing products with wide-ranging applications of immune responses, to help in the evaluation, treatment, or prevention of diseases that can be missed by narrowly  targeted strategies. In addition to SPHERUSOL, Nielsen markets CANDIN® (Candida albicans skin test antigen for cellular immunity). FDA-approved for detecting delayed-type hypersensitivity, CANDIN is also a drug candidate in ongoing investigational studies evaluating its use in the treatment of human papilloma virus (HPV) lesions.

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1.   “Valley Fever: Awareness Is Key.” Centers for Disease Control and Prevention. Centers for Disease Control and Prevention, 27 June 2013. Web. 01 Apr. 2015.
2.   “Press Release.” Centers for Disease Control and Prevention. Centers for Disease Control and Prevention, 28 Mar. 2013. Web. 01 Apr. 2015.
3.   Valdivia L., Nix D, Wright M, et al. Coccidioidomycosis as a common cause of community- acquired pneumonia. Emerg Infect Dis. 2006;12(6):958-962.
4.   “Valley Fever (Coccidioidomycosis) Statistics.” Centers for Disease Control and Prevention. Centers for Disease Control and Prevention, 20 Nov. 2014. Web. 01 Apr. 2015; and “Fact  Sheet.” Centers for Disease Control and Prevention. Centers for Disease Control and Prevention, 18 Dec. 2014. Web. 01 Apr. 2015.