Exhibit 99.1

Calle La Colonia N° 150,

Urb. El Vivero - Santiago de Surco

Tel: 317-6000

Lima, October 23, 2026 

Sirs

Superintendencia del Mercado De Valores – SMV

Lima.-

Reference:     Material Event

In accordance with Article 30 of the Consolidated Text of the Securities Market Law and the Regulations on Material Events and Reserved Information, approved by SMV Resolution No. 005-2014-SMV/01, we hereby report the following:

Today, we became aware of the response submitted by MSRA S.A.C. (the valuation firm appointed to determine the minimum price per share to be considered by Inversiones Aspi S.A. in the Tender Offer for the voting shares issued by Cementos Pacasmayo S.A.A.) to the Superintendency of the Securities Market (the “SMV”), addressing the comments raised by the SMV on the valuation report through Official Letter No. 5332-2026-SMV/11.1, dated October 21, 2026.

According to MSRA S.A.C. in the aforementioned response, all comments raised by the SMV have been addressed, without such response constituting a new valuation report or a modification to the minimum price determined in the valuation report prepared by MSRA S.A.C., which was disclosed to the market on October 14, 2026.

A copy of the aforementioned response submitted by MSRA S.A.C. to the SMV is attached as an Annex to this communication.

Sincerely,

CEMENTOS PACASMAYO S.A.A.

José Félix Villafuerte Mendoza

Stock Exchange Representative

Firmado Digitalmente por:

JOSE FELIX VILLAFUERTE MENDOZA

Fecha: 23/10/2026 10:34:52 a.m