Castle Biosciences Inc

We are a commercial-stage dermatological cancer company focused on providing physicians and their patients with personalized, clinically actionable genomic information to make more accurate treatment decisions. We believe that the traditional approach to developing a treatment plan for certain cancers using clinical and pathology factors alone can be improved by incorporating personalized genomic information. Our non-invasive genomic products utilize proprietary algorithms to provide an assessment of a patient's specific risk of metastasis or recurrence of their cancer, allowing physicians to identify patients who are likely to benefit from an escalation of care as well as those who may avoid unnecessary medical and surgical interventions. Our lead product, DecisionDx-Melanoma, is a proprietary multi-gene expression profile, or GEP, test that predicts the risk of metastasis or recurrence for patients diagnosed with invasive cutaneous melanoma, a deadly skin cancer. We also market DecisionDx-UM, which is a proprietary GEP test that predicts the risk of metastasis for patients with uveal melanoma, a rare eye cancer. Based on the substantial clinical evidence that we have developed, we have received Medicare coverage for both of our products, which represents approximately 50% of our addressable patient population. We also have two proprietary products in late-stage development that address cutaneous squamous cell carcinoma, or SCC, and suspicious pigmented lesions, which are indications with high clinical need in dermatological cancer.

Skin cancer is the most commonly diagnosed cancer in the United States. There are more than 5.5 million new cases of skin cancer diagnosed annually, compared with 1.6 million new cases for all other cancers combined. DecisionDx-Melanoma targets more than an estimated 130,000 patients diagnosed with invasive cutaneous melanoma each year, which we believe is underreported. In addition, our two late-stage proprietary products in development target approximately 200,000 patients diagnosed with SCC with high-risk features and approximately 300,000 patients with suspicious pigmented lesions without a definitive diagnosis of skin cancer. We estimate that the total addressable U.S. market for these three indications is approximately $2.0 billion.

Healthcare providers, predominately dermatologists and surgeons who treat melanoma patients, make nearly all treatment decisions for patients diagnosed with skin cancers based upon their expected risk of metastasis or recurrence. Historically these treatment decisions have been based solely on clinical and pathology factors, such as tumor depth or width, ulceration status, nerve invasion and evidence of metastasis to the sentinel lymph node, or SLN. Physicians use these factors to group, or stage, patients into stage-related populations. The average risk of metastasis within a population then guides treatment decisions for all patients within a respective population. However, an individual patient's risk of metastasis can be significantly different from these stage-related population averages, thereby resulting in some patients receiving unnecessary medical and surgical interventions and some patients being undertreated. This treatment paradigm has led to suboptimal patient care and unnecessary costs to the healthcare system.