At CHEMAS we want to make it easy for you to contact us and enquire about our company. We have listed here the most commonly asked questions we receive and we will answer any enquiries you have as soon as possible by e-mail.

What is TetraAs?

TetraAs is an anti-cancer drug with very few side effects
whose active pharmaceutical ingredient is As4O6


As4O6 (Arsenic hextoxide, molecular weight 395.6)

* Anti-angiogenesis
* Induction of Apoptosis
* Anti-NF-KB activity which is generally increased in advanced cancer

Effective in treating various solid cancers including cervical cancer, lung cancer,
brain cancer, renal cancer, bladder cancer, and maxillary sinus cancer
* Effective in treating blood cancers such as multiple myeloma
* Very effective in reducing cancer pain

* Oral administration
* Almost no side effects or drug intolerance
* Increase in efficacy when used in combination therapy with radiation and other anti-cancer drugs
* Sufficient safety margin
* Possible to develop injectable version
* Very effective in treating cancer pain

As TetraAs’s active pharmaceutical ingredient is arsenic, which is known as a toxic material, should I be concerned about potential toxic issues?

In pre-clinical trials including ADME (absorption, distribution, metabolism, and excretion) evaluation, it was proved that there is almost no toxicity in As4O6, especially in appropriate dose use, and As4O6 is discharged out of the body after a short period of time, 2 or 3 days. After gaining approval for Phase 1 clinical trials from KFDA, Phase 1 clinical trial was conducted at Asan Medical Centre on 15 patients with terminal cancer whose previous surgical operations, anti-cancer chemotherapy and radiotherapy treatments had not suppressed the progress of cancer.

What is the mechanism of TetraAs?

  1. Anti-angiogenesis
  2. Induction of apoptosis
  3. Anti-NF-KB activity which is generally increased in advanced cancer

Are arsenic-based drugs used to treat cancer?

Yes. Arsenic trioxide(As2O3) and As4S4 have been used for cancer treatment. As2O3 is now used as a standard treatment for refractory acute promyelocytic leukemia (APL) and  As4S4 is now used as the treatment for Chronic Myelogenous Leukemia (CML).

Are there any articles on Tetra-arsenic hexoxide?

Yes. Researches on arsenic compounds is being carried out throughout the world and there are thousands of articles addressing the anti-cancer effect of As. In particular, there are 27 articles suggesting that TetraAs developed by CHEMAS has great anti-cancer effects.

Please let us the results of Phase 1 clinical trials of TetraAs?

In Phase 1 clinical trials conducted according to WHO criteria for 4 weeks, any kinds of adverse drug reaction have not been observed. The clinical trial was conducted on 15 patients with terminal cancer whose previous anti-cancer treatments had been unsuccessful (including surgical operations, chemotherapy and radiotherapy). During this trial, 10 out of 15 patients saw the size of their cancer reduced and noted that the progression of their cancer was stalled. Notably, the patients’ quality of life improved significantly.

What is the formulation of TetraAs?

The formulation of TetraAs for the clinical trial is hard gelatin capsule and the pre-clinical trial is under way for injection therapy.

General Questions

If you contact us online, we’ll get back to you within 5 working days. If you need a quicker response, it may be better to call us.


Tel +82.2.3472.7503
Fax +82.2.3472.7507


Samha B/D 3F
502, Bongeunsa-ro
Gangnam-gu, Seoul, KOREA