PowerPoint Presentation


Topical Tirbanibulin Eradication of Periungual Squamous Cell Carcinoma

Angela Yen Moore,1,2 Stephen Moore,1,3,4 Qin He,3 Peter Rady,3 Ayman Grada,5 Stephen Tyring3

1Arlington Research Center, Arlington, TX, USA; 2Baylor University Medical Center, Dallas, TX, USA; 3Department of Dermatology, The University of Texas McGovern Medical School, Houston, TX, USA; 4 Rice University, Houston, TX, USA; 5Grada Dermatology Research LLC, Chesterbrook, PA, USA

INTRODUCTION

• Actinic keratosis (AK) are precancerous 

lesions that if left untreated may lead to 

invasive squamous cell carcinoma (SCC) 1

(Fernandez)

• Tirbanibulin (KX2-391, KX01) is a synthetic, 

highly selective, novel inhibitor of tubulin 

polymerization and Src kinase signaling 

developed as a first-in-class topical 

formulation for the treatment for AK 2 

(Smolinksi)

• Previous Phase I and II studies 

demonstrated that tirbanibulin ointment 1% 

was active against AK lesions on the 

forearm and face or scalp, respectively. 

Local skin reactions (LSRs) were mostly 

transient and mild-to-moderate in severity, 

and tirbanibulin was well tolerated 3 

(DuBois phase I and phase II)

• Tirbanibulin ointment 1% once-daily for 5 

days resulted in higher overall complete AK 

clearance rates at Day 57 than vehicle in 

two Phase III studies (KX01-AK-003: 44% 

vs 5%; KX01-AK-04: 54% vs 13%, 

respectively; p<0.0001) 4 (Blauvelt)

Figure 2:  NCBI-BLAST alignment of sequencing data obtained from the HPV-PCR product

The sequence data obtained from patient’s sample (query) showed 95% identities to the 

prototype HPV 57 DNA deposited into the NCBI GeneBank (sbjct).

• 29-year-old non-smoking male had a biopsy-

confirmed squamous cell carcinoma in situ at 

the distal periungual tip of the left fourth 

fingernail 5

• Previous treatment with imiquimod and 

monthly liquid nitrogen for 6 months had 

failed.

• Tirbanibulin 1% ointment was applied for 5 

days with complete resolution on the fifth day 

without reported erythema, edema, or 

irritation

Figure 1a: Firm verrucous plaque at distal 

periungual tip of the left 4th digit before 

treatment with tirbanibulin 1% ointment

Figure 1b: Complete resolution of squamous 

cell carcinoma after 5 days of topical 

tirbanibulin 1% ointment

Figure 1a Figure 1b

DISCUSSION

CASE REPORT

RESULTS

CONCLUSION

REFERENCES

RESULTS

• HPV typing by nested PCR was performed on 

paraffin-embedded block

METHODS

• HPV 57 was detected (Figure 2),

• Further research on the mechanism of 

tirbanibulin effect on HPV as well as SCC are 

required to confirm these findings.

• Although HPV 57 is most commonly 

associated with common warts, HPV 57 has 

also been reported with oral papillomas, 

esophageal SCC, and cutaneous SCC.

• Even though it is FDA-approved in the U.S. 

for treatment of actinic keratosis, tirbanibulin

ointment may have efficacy on SCC or 

directly on HPV-driven carcinogenesis. 

1. Fernandez Figueras MT. From actinic keratosis to squamous cell carcinoma: 
pathophysiology revisited. J Eur Acad Dermatol Venereol. 2017;31 Suppl 2:5-7. 
doi:10.1111/jdv.14151

2. Smolinski MP, Bu Y, Clements J, et al. Discovery of Novel Dual Mechanism of 
Action Src Signaling and Tubulin Polymerization Inhibitors (KX2-391 and KX2-
361). J Med Chem. 2018;61(11):4704-4719. doi:10.1021/acs.jmedchem.8b00164

3. Smolinski MP, Bu Y, Clements J, et al. Discovery of Novel Dual Mechanism of 
Action Src Signaling and Tubulin Polymerization Inhibitors (KX2-391 and KX2-
361). J Med Chem. 2018;61(11):4704-4719. doi:10.1021/acs.jmedchem.8b00164

4. Blauvelt A, Kempers S, Forman S, Lain E, Bruce S. Tirbanibulin Ointment 1%, a 
Novel Inhibitor of Tubulin Polymerization and Src Kinase Signaling , for the 
Treatment of Actinic Keratosis (AK): Results from Two Pivotal Phase III Studies. J 
of Skin. 2020;4(5):s63-s63. doi:10.25251/skin.4.supp.62

5. Moore AY, Moore S. Topical tirbanibulin eradication of periungual squamous cell 
carcinoma. JAAD Case Reports. 2021;14:101-103. doi:10.1016/j.jdcr.2021.06.013

https://doi.org/10.1111/jdv.14151
https://doi.org/10.1021/acs.jmedchem.8b00164
https://doi.org/10.1021/acs.jmedchem.8b00164
https://doi.org/10.25251/skin.4.supp.62
https://doi.org/10.1016/j.jdcr.2021.06.013