INTRODUCTION

Warts are common epidermal proliferations caused by human papilloma virus (HPV) [1]. There are around 180 strains of HPV known to infect epithelial cells with a predilection toward cutaneous and mucosal surfaces [2]. Morphologically, they are classified as verruca vulgaris, plane, filiform, myrmecia, and mosaic warts. Meanwhile, based on their location, they are divided into plantar, palmar, periungual, and anogenital warts [3]. Despite the availability of a wide range of treatment options ranging from medical agents to surgical excision, they pose a therapeutic challenge because of their recurrent nature [4]. These modalities also carry some drawbacks, such as discomfort, scarring, and inefficiency to treat multiple warts [4,5]. However, immunotherapeutic modalities stimulate the host immune system, mainly cell-mediated immunity, which helps in removing the virus without scars or physical change. Various antigens have been attempted both intralesionally and orally, such as vitamin D, interferon, purified protein derivative (PPD), candida antigen, and oral drugs such as levamisole, zinc, and cimetidine [6].

The MMR vaccine is a live attenuated vaccine that provides protection against measles, mumps, and rubella. The intralesional MMR vaccine aids in the clearance of warts via its immunomodulatory action and the stimulation of both humoral and cell-mediated immunity [7].

The aim of this study was to evaluate the safety and efficacy of intralesional MMR injection in multiple recurrent common warts.

MATERIALS AND METHODS

RESULTS

All 66 patients completed the study. The patients were comparable with respect to age and sex (p > 0.05). The number and location of warts observed in our study were noted (Table 1 and Graph 1). The mean age in the study group (group one) was 29.1 ± 6.46 and, in the control group (group two), it was 28.7 ± 6.72. In our study, we noticed a male predominance in both groups: in the study group, 18 patients (54.55%) and, in the control group, 17 patients (51.52%) (Table 2).

Graph 1: Numbers and sites of the warts.

	Table 1: Numbers and sites of the warts.
	Table 2: Demographic data of the participants.

In the study group, complete clearance was noted in 75.76% (n = 25) (Fig. 1), and partial clearance was noted in 15.5% (n = 5) of the patients. No improvement was noted in 9.1% (n = 3) of the patients (Fig. 2). The mean number of injections required for complete clearance of warts was 3.24.

	Figure 1: A 30-year-old male with warts on the palms and periungual area, showing complete improvement after three sessions of intralesional MMR vaccine.
	Figure 2: A 30-year-old male with multiple common warts on the dorsum of the hand, showing no improvement after four sessions of intralesional MMR vaccine.

In the control group, 78.79% (n = 26) of the patients showed no improvement and 15.15% (n = 5) showed partial improvement. Only 6.06% (n = 2) of the patients showed complete response (Graph 2). The difference in improvement was statistically highly significant (p < 0.01. The complete resolution of distant warts was noted in all patients who had a complete response (Table 3).

Graph 2: Clinical improvement in the cases and controls.

Table 3: Clinical improvement in the cases and controls.

Side Effects

DISCUSSION

Recurrent multiple warts bring social stigma to the patient as well as a challenge to the dermatologist. No single therapy had proven to be completely effective, especially if numerous and distant lesions are considered.

Immunotherapy is a type of biological therapy that employs substances to modify the immune response to help the body to fight an infection, cancer, or autoimmune disease [8].

It is a preferred treatment option due to its effect on both treated and distant warts by inducing HPV-targeted immunity. Intralesional MMR stimulates the adaptive immune system and activates natural killer (NK) cells. It induces a type 1 helper T-cell mediated delayed-hypersensitivity reaction against the antigen and the HPV-infected cells. This causes the destruction of the virus and infected host cells, not only in the treated warts yet also the distant warts [9,10]. The MMR vaccine is more immunogenic than other skin test antigens. Due to the presence of three synergistic viral antigens, a stronger immune response against HPV is generated via the production of cytokines such as interleukin (IL)-2,4,5 and TNF-a [11,12].

Our study revealed that intralesional MMR vaccine is an effective therapy for multiple recurrent common warts. Twenty-five out of the thirty-three patients (75.76%) showed the complete clearance of warts. Comparable results were reported by Chauhan et al., with 82.4% (42/51) of patients showing complete clearance [13]. Similar results were also observed by Nofal et al., with 81.4% of patients achieving complete healing [14]. Intralesional MMR vaccine was found to be safer and more effective than cryotherapy in a study conducted by Abd El-Magiud et al. [15].

During the follow-up period of twelve months, no recurrence was noted in our study group, which was in concordance with Nofal et al., who reported no recurrence in the MMR group after six months [14].

A placebo-controlled study by Awal and Kaur using 0.5 mL of intralesional MMR vaccine every two weeks for a maximum of five sessions showed complete clearance in 68% of patients [12].

A prospective, randomized study by Saini et al. comparing the efficacy of 0.3 mL intralesional MMR vaccine and 100% topical TCA every two weeks for a total of three sessions noted a more than 75% improvement in 49.43% of patients, with 26.44% showing complete response in the MMR group. Meanwhile, 11.11% had a more than 75% improvement, with only 7.94% showing complete resolution in the TCA group [9].

Pain during injection and flu-like symptoms were the side effects reported by our patients. This was comparable to various other studies [9,12,13]. The limitation of our study was a small sample size.

CONCLUSION

Intralesional MMR vaccine for common warts appears to be a simple, safe, and promising treatment modality with a low recurrence rate. The eradication of distant warts with no scarring and pigmentation are its added benefits. However, further, large, well-designed case–control studies are required to delineate the dosing regimen and duration for its effective use.