ZURICH, May 21 (Reuters) - Swiss stocks were set to open slightly lower on Wednesday, with investors' mood marred by losses in the United States and in Asia following disappointing results from heavy machinery firm Caterpillar.
The Swiss blue-chip SMI was seen slipping 0.1 percent at the open, according to the Swiss futures index .
The following are some of the main factors expected to affect Swiss stocks on Wednesday:
* Rating agency Moody's affirmed the ratings of Credit Suisse's deposits and senior debt at A1, but lowered its outlook to negative from stable.
* Novartis said a study showed its once-daily inhaled medicine Ultibro Breezhaler was non inferior to combination therapy in improving health-related quality of life outcomes in patients with moderate-to-severe chronic obstructive pulmonary disease (COPD).
* Julius Baer said it had successfully placed 350 million Swiss francs of subordinated, unsecured debt with private and institutional investors.
* Lonza has guided for core return on net operating assets (RONOA) of 16 percent for 2016. It said all other guidance remains unchanged.
* Swiss Life has appointed Stefan Maechler as new chief investment officer, effective September 1. Maechler, 54, succeeds Patrick Frost who is taking over the role of chief executive at the start of July.
* Evolva said it has achieved a key milestone in its joint development programme of fermentation-based minor steviol glycosides with Cargill and will receive a payment of $1 million.
* SHL Telemedicine posted a 49 percent rise in first-quarter revenues to $10.6 million, generating core profit of $2 million.
* AMS said it has won a patent validity lawsuit launched by Belgium's Melexis concerning a European patent covering magnetic field position sensor products.