RXi’s consumer health development program is based on its proprietary self-delivering RNAi (sd-rxRNA) technology. As a consumer health product, no preventative or therapeutic claims can be made. However, these compounds may be developed more rapidly than therapeutics and, therefore, the path to the market may be shorter and less expensive.
The Company has selected collagenase and tyrosinase as targets for our self-delivering RNAi platform. These two targets are excellent additions to our dermatology franchise because they are relevant for both cosmeceutical and pharmaceutical development. The combined global market potential for cosmetic product development is approximately $200B for skin lightening and skin rejuvenation. RXi's is currently evaluating topical forms of delivery for these compounds.
Collagenases are enzymes that break the peptide bonds in collagen. Matrix metalloproteinase 1 (MMP1) is a collagenase involved in the breakdown of extracellular matrix that specifically cleaves collagen I, II and III. Results from studies show a pronounced reduction in MMP1 mRNA levels that correspond to a similar reduction in MMP1 enzyme activity in cell culture in vitro. RXI-185, an sd-rxRNA compound developed to target Collagenase (MMP1), has been selected to advance into cosmetic product that may improve skin appearance. Selected reduction of MMP1 may be beneficial in the treatment of skin aging disorders, arthritis, acne scarring, blistering skin disorders, corneal erosions, endometriosis and possible cancer metastasis.
Tyrosinase is the key enzyme in the synthesis of melanin. Melanin is produced by melanocytes and is the pigment that gives human skin, hair and eyes their color. The inhibition of tyrosinase can play a key role in the management of diseases such as cutaneous hyperpigmentation disorders such as lentigines (freckles, age spots and liver spots), and possibly melanoma.
RXI-231, an sd-rxRNA compound developed to target Tyrosinase (TYR), has been selected to advance in to cosmetic product development. RXI-231 lead to a visible reduction of pigmentation in melanocytes in a 3-dimensional tissue culture model of human epidermis. Results in this model show that RXI-231 is approximately one hundred times more potent than kojic acid, a well-characterized skin lightening agent. By targeting tyrosinase, a superficial reduction of melanin could potentially change the appearance of the darkened skin spots known as age spots and freckles or lighten the skin overall.
The Company is actively evaluating similar sd-rxRNAs compounds that target TYR and MMP1 for possible therapeutic development.