FOR HEALTHCARE PROVIDERS TREATING HPV+ CANCER

Know Earlier.
Act Sooner.

NavDx Testing During Treatment

for HPV+ Oropharyngeal Cancer

TTMV-HPV DNA clearance kinetics during chemoradiotherapy (CRT) reflect how a patient’s tumor is responding to treatment, often before imaging can detect a change. Serial NavDx® testing during and immediately after treatment can help characterize treatment response, identify molecular residual disease (MRD), and stratify patients by recurrence risk in the critical peri-treatment window.

TTMV-HPV DNA clearance kinetics can inform clinical monitoring and risk stratification during treatment but should not be used currently to modify treatment intensity outside a clinical trial setting. Multiple ongoing trials are evaluating ctHPVDNA-guided changes in treatment intensity and duration.

TTMV Clearance Kinetics During Chemoradiotherapy.

Rapid clearance of TTMV-HPV DNA during CRT is a predictor of favorable treatment response. Multiple independent studies demonstrate that the rate and completeness of TTMV clearance during CRT correlates with disease control outcomes:

      • Week-4 clearance and tumor response: In a prospective study, TTMV-HPV DNA decline at week 4 of CRT correlated with primary tumor volume reduction and nodal response on mid-treatment imaging, providing early on-treatment response data while treatment is still ongoing and potentially modifiable.13
      • End-of-CRT clearance and recurrence risk: In a study of 105 HPV+ OPSCC patients, persistent or rising TTMV-HPV DNA at the end of CRT strongly predicted locoregional recurrence and worse overall survival. Patients who cleared by end of CRT achieved excellent disease-free survival.49
      • Rapid clearance (>95% by week 4): In a 3-year longitudinal study, rapid clearance kinetics, defined as >95% decline by week 4, were associated with improved outcomes and greater likelihood of disease control in patients treated with CRT.7
      • Induction chemotherapy monitoring: ctHPVDNA clearance after the first cycle of induction chemotherapy predicted final disease control more accurately than PET-CT (61.5% vs 7.7% accuracy; p=0.01). All patients with elevated ctDNA after completion of CRT had persistent disease (100% concordance).50

Molecular Residual Disease (MRD).

Detectable TTMV-HPV DNA after the completion of definitive treatment (molecular residual disease) is a result that warrants heightened clinical attention.

      • First post-treatment check: The California Head and Neck Consortium (CHNC) reached strong consensus (84.8%) that the first ctHPVDNA check should occur at 3 months post-treatment.11
      • Persistent positivity and intensified imaging: CHNC strong consensus (93.9%): “In patients with persistent post-treatment ctHPVDNA, more intense imaging surveillance is warranted.”11
      • Prognostic significance: Persistent TTMV-HPV DNA after CRT identifies patients at substantially higher risk of recurrence, providing a clinical decision point for imaging escalation, closer surveillance, or clinical trial enrollment before macroscopic recurrence becomes apparent.11,49

Recurrent/Metastatic Setting.

In patients with recurrent or metastatic (R/M) HPV+ OPSCC, NavDx testing may serve as a dynamic pharmacodynamic biomarker of systemic therapy response.

      • The CHNC consensus (81.9%) recommendations state that “In the M1 setting, ctHPVDNA during therapy offers earlier response assessment, enabling faster pivots.”11
      • In a phase 1/2 prospective trial of cetuximab + nivolumab in R/M HPV+ HNSCC, TTMV-HPV DNA changes preceded imaging confirmation of response or progression. Rising TTMV indicated disease progression, and declining TTMV indicated treatment response, both before CT or PET/CT confirmed the change.52

Key Supporting Studies.

Kim M, et al. | Int J Radiat Oncol Biol Phys. 2025 13

A prospective study evaluating TTMV-HPV DNA kinetics during chemoradiotherapy.

Week-4 TTMV decline correlated significantly with primary tumor volume reduction and nodal response on mid-treatment MRI/PET imaging, providing quantifiable, real-time evidence that TTMV clearance mirrors early tumor response while treatment is still ongoing and potentially modifiable. This study supports the clinical rationale for serial TTMV testing at the mid-treatment timepoint.

Huttinger L, et al. | Oral Oncology. 2025 | N=17 50

Evaluated TTMV-HPV DNA as a predictive biomarker during induction chemotherapy (IC) for HPV+ OPSCC.

TTMV clearance after the first IC cycle predicted final disease control with 61.5% accuracy vs. only 7.7% for PET-CT (p=0.01), a striking demonstration that molecular response outperforms imaging at this early timepoint. Critically, all patients with elevated TTMV after completion of CRT had persistent disease: 100% concordance, establishing residual TTMV as a near-definitive marker of treatment failure in this setting.

Routman DM, Kumar S, et al. | Int J Radiat Oncol Biol Phys. 2022 | N=105 49

In 105 HPV+ OPSCC patients treated with CRT, persistent or rising TTMV-HPV DNA at the end of treatment strongly predicted locoregional recurrence and worse overall survival.

Patients who achieved TTMV clearance by end of CRT demonstrated excellent disease-free survival — establishing end-of-CRT TTMV status as a clinically meaningful indicator of treatment success and a signal for heightened post-treatment surveillance in those who do not clear.

Chera BS, et al. | Clin Cancer Res. 2019 | 3-year longitudinal 7

A 3-year longitudinal study demonstrating that rapid TTMV-HPV DNA clearance kinetics, defined as >95% decline by week 4 of CRT, were associated with improved long-term disease control.

This foundational study established the mechanistic framework for TTMV clearance as a treatment response biomarker during CRT and provided the evidence base for subsequent prospective work on clearance-guided risk stratification.

A favorable circulating TTMV-HPV DNA clearance profile correlates with disease control in OPSCC patients treated with CRT. Kaplan–Meier analysis of RDFS stratified by clinical risk and ctHPV16DNA profile. P value calculated using a two-tailed log-rank test for trend.

Chung CH, et al. | Clin Cancer Res. 2022 52

A phase 1/2 prospective trial evaluating cetuximab + nivolumab in recurrent/metastatic (R/M) HPV+ HNSCC.

Serial ctHPVDNA measurements preceded imaging confirmation of both response and progression — rising ctHPVDNA indicated disease progression and declining ctHPVDNA indicated treatment response, both before CT or PET/CT confirmed the change. This is the first prospective pharmacodynamic biomarker evidence supporting ctHPVDNA monitoring during systemic therapy in R/M disease and was cited by the CHNC as the basis for their M1-setting consensus statement.

NavDx Testing During Treatment

for HPV+ Anal Cancer

TTMV-HPV DNA clearance kinetics during chemoradiotherapy (CRT) reflect how a patient’s tumor is responding to treatment, often before imaging can detect a change. Serial NavDx testing during and immediately after treatment can help characterize treatment response, identify molecular residual disease (MRD), and stratify patients by recurrence risk in the critical peri-treatment window.

Expert consensus guidance and/or recommendations on use of the NavDx test in particular and ctHPVDNA in general during active treatment for ASCC, analogous to the CHNC consensus established for OPSCC, does not yet exist. The evidence below supports the use of TTMV-HPV DNA as an informational biomarker of treatment response, particularly in the advanced/metastatic setting where earlier response assessment can meaningfully influence treatment decisions. Use in conjunction with clinical judgment and standard imaging.

Post-CRT Molecular Residual Disease.

In the curative CRT setting, residual ctHPVDNA after treatment completion is associated with rapid disease progression:

      • In a proof-of-concept study of 33 stage II–III ASCC patients, 3/18 patients had detectable ctHPVDNA after CRT. All 3 developed rapid metastatic relapse within 4.3 months. Of the 15 ctDNA-negative patients after CRT, only 1 (7%) relapsed. Disease-free survival was strongly associated with post-CRT ctDNA status.53
      • In the foundational 2025 NavDx ASCC study, 76% of patients with a positive pre-treatment TTMV Score showed resolution within 3 months of completing treatment. TTMV resolution correlated with significantly better recurrence-free survival, providing a measurable biological endpoint for treatment response.⁴

Advanced and Metastatic ASCC: Systemic Therapy Monitoring.

Two independent studies demonstrate that TTMV-HPV DNA kinetics during systemic therapy in advanced ASCC predict clinical benefit earlier than imaging:

      • In a phase II trial and long-term responder cohort (N=32 advanced ASCC), a decrease in TTMV Score at 3 weeks was associated with clinical benefit from pembrolizumab (p=0.008). At 6 weeks, patients with a declining TTMV Score had median PFS of 3.0 months vs. 0.7 months in those with rising scores (HR 0.37; p=0.04).45
      • In one remarkable case, TTMV-HPV DNA became undetectable 18 weeks before radiographic complete response was confirmed at week 45, demonstrating that molecular response can substantially precede radiographic evidence of cure. 45
      • In a prospective ancillary study to a phase II trial (N=59 advanced HPV16+ ASCC treated with DCF chemotherapy), post-chemotherapy ctDNA was the strongest predictor of PFS (HR 5.5; 95% CI 2.1–14.3; p<0.001) and 1-year OS (87% undetectable vs. 50% detectable; OR 7.0; p=0.02).54

Key Supporting Studies.

Cabel L, Jeannot E, et al. | Clin Cancer Res. 2018 | N=33 53

A proof-of-concept study of 33 stage II–III ASCC patients undergoing definitive CRT. Of 18 patients evaluable for post-CRT ctHPVDNA status, 3 had detectable ctDNA. All 3 developed rapid metastatic relapse within a median of 4.3 months. Of the 15 ctDNA-negative patients, only 1 (7%) relapsed. Disease-free survival was strongly associated with post-CRT ctDNA status (p<0.0001). This was the first study to establish post-CRT ctHPVDNA as a powerful early indicator of treatment failure in ASCC and remains the foundational evidence for molecular residual disease monitoring in this disease.

Bernard-Tessier A, Jeannot E, et al. | Clin Cancer Res. 2019 | N=59 54

A prospective ancillary study to a phase II trial of DCF chemotherapy in 59 advanced HPV16+ ASCC patients. Post-chemotherapy ctDNA was the strongest independent predictor of progression-free survival (HR 5.5; 95% CI 2.1–14.3; p<0.001) and 1-year overall survival (87% in ctDNA-undetectable vs. 50% in ctDNA-detectable patients; OR 7.0; p=0.02), retaining significance in multivariate analysis. This study validated ctHPVDNA as a biomarker of chemotherapy response in advanced ASCC and established the magnitude of the survival gap between molecular responders and non-responders.

Huffman BM, Singh H, Ali LR, et al. | J Immunother Cancer. 2024 | N=32 45

A phase II clinical trial and long-term responder cohort analysis of pembrolizumab in advanced ASCC. A decrease in TTMV Score at 3 weeks was associated with clinical benefit (p=0.008); at 6 weeks, median PFS was 3.0 vs. 0.7 months for declining vs. rising TTMV (HR 0.37; p=0.04), enabling early identification of pembrolizumab non-responders before clinical or radiographic deterioration. In one complete responder, TTMV-HPV DNA became undetectable 18 weeks before radiographic CR was confirmed at week 45.

Kabarriti R, Lloyd S, Jabalee J, et al. | Cancers (Basel). 2025 | N=117 ⁴

In the post-treatment surveillance cohort, 76% of patients who were TTMV-positive at pre-treatment showed resolution of detectable TTMV within 3 months of completing CRT. TTMV resolution correlated with significantly better recurrence-free survival (log-rank p<0.0001), confirming that post-CRT TTMV clearance is a meaningful biological endpoint. This study also links pre-treatment and during-treatment data: the pre-treatment baseline is the reference point against which post-treatment clearance or persistence is measured, underscoring the importance of baseline testing before therapy begins.

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