FOR HEALTHCARE PROVIDERS TREATING HPV+ CANCER

Know Earlier.
Act Sooner.

NavDx Testing in Pre-Treatment

for HPV+ Oropharyngeal Cancer

A pre-treatment NavDx test serves three distinct and clinically important purposes: confirming HPV+ tumor etiology (especially when tissue-based testing is inconclusive); confirming HPV genotype; and establishing a baseline that adds prognostic and clinical context to future testing. Expert consensus from the California Head and Neck Consortium (CHNC) endorses these applications.11 While pre-treatment testing is ideal, it is not required to use the NavDx test during treatment or for post-treatment surveillance; you can begin testing at any point in the patient’s care journey.

CHNC Expert Consensus.

“Obtaining baseline/pre-treatment ctHPVDNA levels is important for post-treatment surveillance.”

— California Head and Neck Consortium, JCO Oncology Practice 2025 | 81.8% strong consensus

“ctHPVDNA can confirm HPV+ OPC etiology in cases with indeterminate biopsies or occult primary cancers.”

— California Head and Neck Consortium, JCO Oncology Practice 2025 | 90.9% strong consensus

Use Case 1: Confirm HPV+ Etiology.

Tissue-based HPV testing has important limitations. p16 IHC, the most common proxy, can overestimate HPV positivity: a meaningful proportion of OPSCC patients test p16-positive despite having a tumor that is not truly HPV-driven. NavDx testing directly detects circulating TTMV-HPV DNA and is not subject to this p16 cross-reactivity.
NavDx is especially valuable when tissue-based results are inconclusive or unavailable:

      • Lateral neck mass workup: In a prospective study of 138 patients presenting with a lateral neck mass suspicious for HPV+ OPSCC, TTMV-HPV DNA sensitivity was 95.7% and specificity 97.8%, outperforming fine needle aspiration (FNA) by more than 18 percentage points (FNA sensitivity: 76.7%).14
      • Non-diagnostic FNA: When FNA yields inadequate material for cytology (up to 23% of cystic neck mass FNAs), NavDx testing can serve as a non-invasive confirmatory step. PPV was 100% in patients with non-diagnostic FNA results. A positive NavDx result in this setting essentially confirms HPV+ OPSCC.15
      • Indeterminate tissue/insufficient biopsy: NavDx testing can confirm HPV status and provide a pre-treatment baseline when tissue is insufficient for p16 or HPV staining, avoiding repeat FNA or operative biopsy.16
      • Occult primary (squamous cell carcinoma of unknown primary): NavDx testing sensitivity for identifying HPV+ OPSCC as the occult primary source is 90.9%–95.7%.46
      • HPV tumor status accuracy: TTMV-HPV DNA was detected in 92% of HPV+ OPSCC patients and 0% of HPV− OPSCC patients in a multi-institutional validation study, confirming strong concordance with rigorous HPV genotyping.9

Use Case 2: Identify the Tumor HPV Genotype.

NavDx testing identifies specific HPV genotypes (HPV-16, -18, -31, -33, -35), not simply “HPV-positive.” Genotype information may have implications for prognosis and for the interpretation of subsequent surveillance results, as NavDx test performance has been most extensively characterized for HPV16+ tumors.

Use Case 3: Tracking Treatment Response.

Approximately 10% of HPV+ OPSCC patients have undetectable baseline TTMV-HPV DNA levels, a finding that can itself carry prognostic significance. For the remaining 90%, a pre-treatment baseline establishes a reference that may make in-treatment test results more meaningful.

 

Clearance patterns during chemoradiotherapy correlate with long-term disease control. The rate at which TTMV-HPV DNA clears during treatment provides insight into treatment efficacy that imaging alone cannot offer.⁷

Key Supporting Studies.

Ferrandino RM, et al. | JAMA Otolaryngol Head Neck Surg. 2024 | N=138 14

A prospective study of 138 patients presenting with a lateral neck mass suspicious for HPV+ OPSCC. TTMV-HPV DNA sensitivity was 95.7% and specificity 97.8% for confirming HPV+ OPSCC, outperforming fine needle aspiration (FNA) by more than 18 percentage points (FNA sensitivity: 76.7%). In the subset with non-diagnostic FNA, NavDx PPV was 100%, establishing it as a reliable non-invasive confirmatory tool when cytology is inconclusive or inadequate.

Papazian M, et al. | Head & Neck. 2025 15

Evaluated circulating tumor HPV DNA in patients with cystic lateral neck masses and non-diagnostic FNA results, a scenario occurring in up to 23% of cystic neck mass FNAs. NavDx testing PPV was 100% in this population: a positive result in the setting of a non-diagnostic FNA essentially confirms HPV+ OPSCC, providing high-confidence diagnosis without repeat invasive procedures.

Mijares K, et al. | Am J Surg Pathol. 2023 9

A multi-institutional validation study assessing TTMV-HPV DNA concordance with rigorous tissue-based HPV genotyping. TTMV-HPV DNA was detected in 92% of HPV+ OPSCC patients and 0% of HPV− OPSCC patients, confirming strong concordance with gold-standard genotyping and establishing that NavDx testing does not produce false positives in HPV− disease.

Kais M, et al. | Frontiers in Oncology. 2024 46

Evaluated NavDx in the workup of squamous cell carcinoma of unknown primary (SCUP) with cervical lymphadenopathy. NavDx testing sensitivity for identifying HPV+ OPSCC as the occult primary source was 90.9%–95.7%, supporting its use as a non-invasive confirmatory tool when standard workup fails to identify the primary lesion.

Chera BS, et al. | Clin Cancer Res. 2019 ⁷

A 3-year longitudinal study demonstrating that rapid TTMV-HPV DNA clearance during chemoradiotherapy (defined as >95% decline by week 4 of CRT) correlated with improved long-term disease control. This foundational study established TTMV clearance kinetics as a treatment response biomarker and confirmed that a pre-treatment baseline is necessary to calculate meaningful clearance rates throughout and after treatment

NavDx Testing in Pre-Treatment

for HPV+ Anal Cancer

A pre-treatment NavDx test serves three distinct and clinically important purposes: confirming HPV+ tumor etiology (especially when tissue-based testing is inconclusive); confirming HPV genotype; and establishing a baseline that adds prognostic and clinical context to future testing. While pre-treatment testing is ideal, it is not required to use the NavDx test during treatment or for post-treatment surveillance; you can begin testing at any point in the patient’s care journey.

Use Case 1: Confirm HPV+ Etiology.

Approximately 90% of anal squamous cell carcinomas are HPV-driven (predominantly HPV16/18). NavDx testing can confirm HPV association when tissue biopsy results are equivocal and provides specific HPV genotype information (HPV-16, -18, -31, -33, -35) that tissue testing may not always capture.

      • Distinguishes ASCC from HSIL: In patients with HIV, a population at elevated ASCC risk, the NavDx test’s specificity was 100% for differentiating patients with ASCC from patients with anal high-grade squamous intraepithelial lesions (HSIL).48 A positive NavDx result in a high-risk patient with HSIL is highly indicative of malignant transformation rather than persistent precancerous lesions.
      • Approximately 3% NavDx positivity rate was found in nearly 200 HSIL patients. Those who test positive are being monitored for ASCC progression, reinforcing specificity in pre-malignant anal disease.

Use Case 2: Identify the Tumor HPV Genotype.

NavDx testing identifies specific HPV genotypes (HPV-16, -18, -31, -33, -35), not simply “HPV-positive.” Genotype information may have implications for prognosis and for the interpretation of subsequent surveillance results, as NavDx test performance has been most extensively characterized for HPV16+ tumors.

Use Case 3: Tracking Treatment Response.

In the two multi-site ASCC studies, TTMV-HPV DNA was detected in 85% of patients at pre-treatment4 and 86.2% in the larger follow-up cohort5, confirming TTMV as a reliable biomarker across patient populations.

      • Baseline resolution predicts outcomes: Among patients with a positive pre-treatment TTMV Score, 76% showed resolution of detectable TTMV within 3 months post-treatment. TTMV Score resolution correlated with significantly better recurrence-free survival, providing early prognostic information that imaging alone cannot provide at 3 months.4
      • Persistent post-treatment TTMV: Patients with detectable TTMV-HPV DNA after treatment had significantly worse recurrence-free survival than those who cleared.4 Knowing the pre-treatment baseline allows accurate characterization of post-treatment persistence vs. clearance.
      • Treatment response monitoring during CRT: Serial TTMV-HPV DNA measurement during chemoradiotherapy can stratify patients by response as early as mid-treatment. Early undetectable TTMV indicates high likelihood of complete response; persistently detectable TTMV through end of treatment indicates a higher risk of persistent/progressive disease.4,13,49,50

Key Supporting Studies.

Kabarriti R, Lloyd S, Jabalee J, et al. | Cancers (Basel). 2025 (N=117; 7 centers)4 and 2026 (N=233; 10 centers)5

The foundational multi-site NavDx ASCC studies. In Kabarriti 2025 (N=117, 7 centers), pre-treatment TTMV-HPV DNA was detected in 85% of patients, confirming it as a reliable baseline biomarker in ASCC. In Kabarriti 2026 (N=123 patients with a pre-treatment draw, 10 centers), the pre-treatment detection rate was 86.2% (95% CI 78.8–91.7%). Across both studies, 76% of patients who were TTMV-positive at baseline showed resolution within 3 months post-treatment, and TTMV resolution correlated with significantly better recurrence-free survival, providing an early prognostic indicator that standard imaging at 3 months cannot.

Ellsworth G, et al. | J Acquir Immune Defic Syndr. 2023 48

The study evaluated NavDx specificity in HIV-positive patients with anal high-grade squamous intraepithelial lesions (HSIL), a population at elevated risk of ASCC progression. NavDx specificity was 100% for distinguishing ASCC from HSIL in this high-risk group, confirming that a positive NavDx result in an HIV+ patient with HSIL is highly indicative of malignant transformation rather than a pre-malignant lesion. This study supports NavDx as a triage tool in HIV-positive surveillance populations where distinguishing HSIL from invasive cancer is a key clinical challenge.

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