* Roche wins expanded approvals for cancer, arthritis drugs
* New indications seen boosting sales
* Medicines are part of Roche's biosimilars defence strategy (Adds details, company comment throughout)
ZURICH, Sept 22 (Reuters) - Roche received expanded European approvals for its Actemra medication in giant cell arteritis (GCA) and for Gazyvaro in people with previously untreated advanced follicular lymphoma, the Swiss drugmaker said on Friday.
The medicines have been approved in other settings for years, but Roche is pushing to expand or accelerate their use as the Swiss company's three main medicines -- Avastin, Rituxan and Herceptin, with $20 billion in annual sales -- come under threat of increasing competition from cheaper biosimilar copies.
In 2016, sales of Actemra rose 16 percent to 1.7 billion Swiss francs ($1.76 billion) for patients with rheumatoid arthritis but are due to more than double between now and 2024.
Sales of Gazyvaro, a blood cancer medicine Roche developed to follow its blockbuster Rituxan that this year lost patent protection, rose 52 percent to 196 million francs last year.
Zuercher Kantonalbank analyst Michael Nawrath said Friday's broader approval is key to Gazyvaro, known as Gazyva in the United States, eventually hitting peak annual sales of $1.5 billion.
Giant cell arteritis is a rare immunological disease in which blood vessels, mostly in the head, become inflamed. Actemra, first approved in 2010 for rheumatoid arthritis, won U.S. Food and Drug Administration approval for the rare condition in May.
"As the first effective non-steroid therapy for GCA, Actemra has the potential to fundamentally change how this condition is treated," Sandra Horning, Roche's chief medical officer, said.
The medicine also goes by the name RoActemra.
While Gazyvaro has been approved in Europe to treat follicular lymphoma as a second-line therapy in cases where Rituxan failed, clearing this latest regulatory hurdle allows Roche to deploy the medicine as a first-line therapy for patients just diagnosed with the most common form of non-Hodgkin lymphoma.
In Roche's study, the risk of disease progression or death was reduced by 29 percent in patients getting Gazyvaro compared to those who got Rituxan. ($1 = 0.9680 Swiss francs) (Reporting by Joshua Franklin, editing by John Revill and Michael Shields)