The purpose of this study is evaluate the efficacy and safety of Botulax® in the treatment of Essential blepharospasm.

Multi-center, single arm, open-label, Phase IV clinical trial to evaluate the efficacy and safety of Botulax® in Subjects with essential blepharospasm

Inclusion Criteria:

1. Men and women at the age of 18 or older
2. Subjects diagnosed with essential blepharospasm with Jankovic Rating Scale (JRS) frequency and severity sum score ≥2 at screening
3. Individuals who agree to participate in the clinical study and voluntarily sign the written informed consent form
4. Subjects who are cooperative, have a good understanding of the clinical study, and can comply with study procedures until the end of the study

Exclusion Criteria:

1. Subjects who had received surgery such as orbicularis oculi resection or facial nerve block for the treatment of the study indication
2. Subjects with a history of hypersensitivity reactions to any of the components of the investigational product (botulinum toxins, serum albumin, etc.)
3. Subjects with secondary blepharospasm
4. Subjects with the hemifacial spasm
5. Subjects on treatment with muscle relaxants, benzodiazepines, anticholinergics, or benzamides who had changes in medication within 4 weeks prior to screening or have been on stable medication but are expected to have changes in medication while participating in the study
6. Subjects who administered any of the following drugs within 7 days prior to screening: drugs with muscle relaxation activity such as aminoglycoside antibiotics or other antibiotics (spectinomycin HCl, polypeptide antibiotics, tetracycline antibiotics, lincomycin antibiotics)
7. Subjects who administered medications similar to the investigational product (botulinum toxin type A) within 12 weeks
8. Subjects with systemic neuromuscular junction disorders: myasthenia gravis, Lambert-Eaton syndrome, or amyotrophic lateral sclerosis
9. Pregnant and lactating women
10. Women of childbearing potential who are planning to become pregnant within the next 3 months or are not using an appropriate method of contraception (contraceptive methods with an annual failure rate of less than 1% if used properly and continuously, including implant, injection, oral contraceptive, at least one barrier method such as intrauterine device [IUD], hormone IUD, abstinence, or vasectomized partner)