Sun Pharmaceutical Laboratories Ltd The appellant, in the case of Sun Pharmaceuticals Ltd v. Hetero Healthcare Ltd. & Anr. filed a lawsuit alleging trademark infringement and passing off and asking for a decree of permanent injunction prohibiting the respondent from using the brand "LETERO" in relation to the in question pharmaceutical product. The appellant challenged an order by the Commercial Court dismissing its application under Order 39 Rules 1 & 2 of the Code of Civil Procedure, 1908. It is alleged that Sun has been utilizing the trademark "LETROZ" since 2001 for a generic medication used as a second-line therapy for advanced breast cancer.
According to the Commercial Court, it is obvious that the mark used by SUN consists only of the first six letters of the INN. Keeping the aforementioned in mind, it must be determined whether the trademarks are comparable. The Court determined that the appellant in the current case cannot be permitted to monopolize the INN "LETROZOLE" based on the Schering Corporation & Ors. v. Alkem Laboratories Ltd. decision.
The High Court agreed with the Commercial Court's assessment that there isn't much room for doubt or deceit in the buyer's mind when it comes to the medicine. It followed the reasoning in Panacea Biotec Ltd. v. Recon Ltd., where it was decided that a manufacturer cannot assert any distinctiveness or exclusivity where the name is taken from or coined from the term of the primary substance utilized in the creation of the drug.
The Court reaffirmed that, in the event of a passing-off lawsuit, the resemblance of the opposing marks must be considered along with any potential for confusion or deceit. In Cadila Health Care Ltd. v. Cadila Pharmaceuticals Ltd., the Supreme Court ruled that the parties' products would be bought by both literate and illiterate citizens of the towns and villages, and that the issue must be viewed from the perspective of "a man of average intelligence and imperfect recollection." The court ruled that it was impossible to compare a buyer of goods in India to one who made their purchase in England. It was discovered that the medications have very diverse adverse effects, according to their findings. As a result, the test should be applied strictly because any mistake on the part of the consumer could cause serious injury.
Lastly the court noted that "In a case, where a drug necessarily has to be prescribed by a registered medical practitioner, especially, for the treatment of an ailment as serious as breast cancer, it is difficult to accept that the said medical practitioner is likely to be confused because the initial three letters of the marks – which are derived from the API – are same.LETERO' is a registered trademark of HETERO, and the drug under the said mark has been sold since 2007. SUN has not filed any document or evidence to remotely suggest that any person has gotten confused because of the alleged deceptive similarity between the two marks.”