Roche, the Swiss-based multinational drug maker, said its group sales for the first quarter fell to CHF14.4 billion ($15.8 billion) from CHF15.32 billion last year, a decline of 6%. At constant exchange rates, quarterly sales increased 2% as strong demand for newer medicines as well as diagnostics products including immunodiagnostics, clinical chemistry tests and advanced staining solutions more than offset the anticipated decline in Covid-19-related sales and the impact of biosimilar/generic erosion. After the latest quarter, the impact of the drop in Covid-19-related sales is largely over an…