Merck (MRK) official guidance

| Share count (assuming dilution) | Approximately 2.48 billion | Approximately 2.48 billion |

We assume approximately 2.48 billion shares outstanding.

| Share count (assuming dilution) | Approximately 2.48 billion | Approximately 2.48 billion |

We assume approximately 2.48 billion shares outstanding.

| Share count (assuming dilution) | Approximately 2.48 billion | Approximately 2.48 billion |

We assume approximately 2.48 billion shares outstanding.

| Share count (assuming dilution) | Approximately 2.48 billion |

The Company now expects the full-year non-GAAP effective income tax rate to be between 32.0% and 33.0%, including the impact of the non-tax-deductible one-time charges for the acquisitions of Cidara and Terns.

We now expect a full-year tax rate between 35% and 36%, which reflects the non-tax-deductible one-time charge for Terns.

The Company now expects the full-year non-GAAP effective income tax rate to be between 35.0% and 36.0%, including the impact of the non-tax deductible one-time charges for the acquisitions of Cidara and Terns.

We assume a full year tax rate between 23.5% and 24.5%, which reflects the non-tax deductible one-time charge for Sedera.

The Company continues to expect the full-year non-GAAP effective income tax rate to be between 23.5% and 24.5% including the impact of the non-tax-deductible one-time charge for the acquisition of Cidara.

We assume a full-year tax rate between 23.5% and 24.5%, which reflects the non-tax-deductible one-time charge for Cidara.

| Non-GAAP Effective tax rate2 | 23.5% to 24.5% |

The Company now expects full-year 2026 non-GAAP EPS to be between $2.77 and $2.82, including a positive impact from foreign exchange of approximately $0.15 per share at mid-October 2026 exchange rates. This range includes one-time charges of $9.0 billion, or $3.62 per share, related to the acquisition of Cidara; $5.7 billion, or $2.31 per share, related to the acquisition of Terns; and $400 million, or $0.12 per share, related to the global license agreement with SciBrunch.

Taken together, we expect EPS of $2.66-$2.76, with a midpoint of $2.71, including a positive impact from foreign exchange of approximately $0.15 using mid-July rates.

The Company now expects full-year 2026 non-GAAP EPS to be between $2.66 and $2.76, including a positive impact from foreign exchange of approximately $0.15 per share at mid-July 2026 exchange rates.

Taken together, we expect EPS of $5.04-$5.16, including a positive impact from foreign exchange of approximately $0.10 using mid-April rates.

The Company now expects full-year 2026 non-GAAP EPS to be between $5.04 and $5.16, including a positive impact from foreign exchange of approximately $0.10 per share at mid-April 2026 exchange rates.

Taken together, we expect EPS of $5-$5.15, with a midpoint of $5.08, including a positive impact from foreign exchange of approximately $0.10 using mid-January rates.

| Non-GAAP EPS2\*\*\* | $5.00 to $5.15 |

| Non-GAAP Gross margin3 | Approximately 81% | Approximately 81% |

Gross margin is now assumed to be approximately 81%, reflecting higher inventory reserves.

| Non-GAAP Gross margin3 | Approximately 81% | Approximately 82% |

Our growth margin assumption remains approximately 82%.

| Non-GAAP Gross margin3 | Approximately 82% | Approximately 82% |

Our gross margin assumption is approximately 82%.

| Non-GAAP Gross margin2 | Approximately 82% |

| Non-GAAP Operating expenses3** | $42.4 billion to $42.9 billion | $42.0 billion to $42.7 billion |

Operating expenses are expected to be between $42 billion and $42.7 billion. This range includes $5.8 billion for the upfront charge for Terns and investment to advance MK-4208.

| Non-GAAP Operating expenses3** | $42.0 billion to $42.7 billion | $36.0 billion to $36.8 billion |

Operating expenses are assumed to be between $36 billion-$36.8 billion.

| Non-GAAP Operating expenses3** | $36.0 billion to $36.8 billion | $35.9 billion to $36.9 billion |

Operating expenses are assumed to be between $35.9 billion and $36.9 billion, which includes a one-time charge of approximately $9 billion related to the acquisition of Cidara.

| Non-GAAP Operating expenses2\*\* | $35.9 billion to $36.9 billion |

| Non-GAAP Other (income) expense, net3 | Approximately $1.4 billion expense | Approximately $1.4 billion expense |

Other expense, which now includes the financing costs for Terns, is expected to be approximately $1.4 billion.

| Non-GAAP Other (income) expense, net3 | Approximately $1.4 billion expense | Approximately $1.3 billion expense |

Other expense is expected to be approximately $1.3 billion.

| Non-GAAP Other (income) expense, net3 | Approximately $1.3 billion expense | Approximately $1.3 billion expense |

Other expense of approximately $1.3 billion includes financing costs for Cidara and Verona.

| Non-GAAP Other (income) expense, net2 | Approximately $1.3 billion expense |

The Company now anticipates full-year 2026 sales to be between $66.8 billion and $67.3 billion, including a positive impact from foreign exchange of approximately 1% at mid-October 2026 exchange rates.

We have raised and narrowed our full-year revenue guidance range to be between $66.3 billion and $67.3 billion, representing growth of 2%-4%, including a positive impact from foreign exchange of approximately one percentage point using mid-July rates.

The Company is raising and narrowing the range for its full-year sales outlook and now anticipates full-year 2026 sales to be between $66.3 billion and $67.3 billion, including a positive impact from foreign exchange of approximately 1% at mid-July 2026 exchange rates.

We now expect revenue to be between $65.8 billion-$67 billion, representing growth of 1%-3%, including a positive impact from foreign exchange of approximately 1 percentage point using mid-April rates.

The Company now anticipates full-year 2026 sales to be between $65.8 billion and $67.0 billion, including a positive impact from foreign exchange of approximately 1% at mid-April 2026 exchange rates.

We expect revenue to be between $65.5 billion and $67 billion, representing growth of 1%-3%, including a positive impact from foreign exchange of approximately one percentage point using mid-January rates.

| Sales\* | $65.5 billion to $67.0 billion |

We are on pace for approximately $3 billion in share repurchases this year, as previously communicated.

We are on pace for approximately $3 billion of share repurchases this year, as previously communicated.

Our guidance assumes approximately $3 billion of share repurchases, and we remain committed to not having excess cash build on the balance sheet.

**Includes one-time R&D charges of $9.0 billion** for the acquisition of Cidara Therapeutics, Inc. (Cidara) and $5.7 billion for the acquisition of Terns.

This range includes $5.8 billion for the upfront charge for Terns and investment to advance MK-4208.

**Includes one-time R&D charges of $9.0 billion** for the acquisition of Cidara Therapeutics, Inc. (Cidara) and $5.7 billion for the acquisition of Terns.

Operating expenses are assumed to be between $35.9 billion and $36.9 billion, which includes a one-time charge of approximately $9 billion related to the acquisition of Cidara.

This range includes a one-time charge of approximately $9.0 billion, or approximately $3.65 per share, as well as approximately $0.30 per share of related financing and operational costs, related to the acquisition of Cidara.