Current treatments for HPV available in Brazil and the importance of new combination therapies.
Currently, there are some ways to prevent human papillomavirus (HPV) infection. This virus is responsible for cervical cancer, considered the fourth most frequent type of cancer in the world and the third leading cause of cancer death in women (1). The quadrivalent HPV vaccine, which protects against the 4 most common types of the virus (6, 11, 16 and 18) is available today in Brazil free of charge by SUS (Brazilian Unified Health System) and can be administered to boys and girls aged 9 to 14, in men and women aged 9 to 26 years living with HIV or AIDS, patients who have received organ transplants, bone marrow transplants, and people undergoing cancer treatment. In 2021 immunosuppressed women aged 26 to 45 years were also included (2).
However, for people who have already come into contact with HPV or who have developed diseases associated with this virus, such as precancerous lesions or cancer in the cervix, vagina, vulva, anus, penis, oropharynx and mouth, preventive methods are no longer equally effective. Prevention can also be done through periodic exams, such as the Papanicolaou test, a gynecological cytology exam performed on women aged 25 and over with an active sexual life, which detects pre-cancerous lesions caused by HPV infection (3).
In cases of people who have already come into contact with HPV, the main forms of treatment are surgery and chemotherapy, depending on the stage of evolution of the disease.
The most used chemotherapeutic in the treatment of cervical cancer is cisplatin, which has good results in tumor control. However, through scientific studies, it was noticed that high doses of this substance can negatively impact antitumor responses, in addition to inducing severe adverse effects. Thereby, it is understood the need to discover and use new less invasive therapeutic strategies that generate a better quality of life for the patient.
ImunoTera has developed active immunotherapies that are capable of reprogramming the immune system, teaching the body to “see” cancer and fight it specifically, without harming healthy cells. These immunotherapies are actually therapeutic vaccines, given in two doses, that generate a highly specialized T cell immune response to kill infected cells or cancer cells.
In work recently published in the International Journal of Biological Sciences, ImunoTera team explored the combination of its therapeutic vaccines and cisplatin-based chemotherapy in the treatment of advanced-stage tumors caused by HPV. The study used preclinical models (laboratory animals) of cervical and oropharyngeal cancer caused by HPV-16. The results showed that treatment based only on chemotherapy partially controlled the tumor and triggered high toxicity, mainly in the kidneys and liver. On the other hand, the association of chemotherapy with therapeutic vaccines from ImunoTera led to the cure of most animals that had tumors, with a reduction in the dose of cisplatin and, consequently, its toxic effects. In addition, an immune memory response (local and systemic) to cancer-associated antigens was also observed, preventing the recurrence of new tumors.
Finally, it is possible to conclude that the synergistic effect of this combination therapy is promising for the treatment of cancer induced by HPV, and the results obtained may serve as a basis for clinical studies with patients diagnosed with cervical cancer (1).
References
1. Bruna Felício Milazzotto Maldonado Porchia, Luana Raposo de Melo Moraes Aps, Ana Carolina Ramos Moreno, Jamile Ramos da Silva, Mariângela de Oliveira Silva, Natiely Silva Sales, Rubens Prince dos Santos Alves, Clarissa Ribeiro Reily Rocha, Matheus Molina Silva, Karine Bitencourt Rodrigues, Tácita Borges Barros, Roberta Liberato Pagni, Patrícia da Cruz Souza, Mariana de Oliveira Diniz, Luís Carlos de Souza Ferreira. Active immunization combined with cisplatin confers enhanced therapeutic protection and prevents relapses of HPV-induced tumors at different anatomical sites.