Sponsor decision to terminate study based on results of parent study GBT2104-131.

This study is an open-label study to evaluate the safety of long-term administration of inclacumab in participants with sickle cell disease (SCD). Participants in this study will have completed a prior study of inclacumab.

The study will include approximately 520 adult and adolescent participants (≥ 12 years of age) with SCD.

All participants will receive inclacumab 30 mg/kg administered intravenously every 12 weeks.

Inclusion Criteria:

Participants who meet all the following criteria will be eligible for study enrollment:

1. Male or female participant with SCD who participated and received study drug in a GBT-Sponsored inclacumab clinical study.

2. Participant has completed the originating inclacumab study within 30 calendar days of the Day 1 Visit. Participants who discontinued study drug in the originating study due to a non-study drug-related AE, but who remained on study, may be eligible for treatment in this study provided the AE does not pose a risk for treatment with inclacumab.

3. Female participants of childbearing potential are required to have a negative urine pregnancy test prior to dosing on Day 1.

   Note: Female participants who become of childbearing potential during the study must be willing to have a negative urine pregnancy test to remain in the study.

4. If sexually active, female participants of childbearing potential must consistently use highly effective methods of contraception consistently throughout the study and for at least 165 days after the last dose of study drug. If sexually active, male participants must use barrier methods of contraception until 165 days after the last dose of study drug.

5. Participant has provided written informed consent/assent. For underage participants, both the consent of the participant's legal representative or legal guardian and the participant's assent (where applicable) must be obtained based on local requirement.

Exclusion Criteria:

Participants meeting any of the following exclusion criteria will not be eligible for study enrollment:

1. Female participant who is breastfeeding or pregnant.
2. Participant had an infusions-related reaction (IRR) in the originating inclacumab clinical study.
3. Participant withdrew consent from the originating inclacumab clinical study.
4. Participant was lost to follow-up from the originating inclacumab clinical study.
5. Participant has any medical, psychological, safety, or behavioral conditions that, in the opinion of the Investigator, may confound safety interpretation, interfere with compliance, or preclude informed consent.

Pfizer will provide access to individual de-identified participant data and related study documents (e.g. protocol, Statistical Analysis Plan (SAP), Clinical Study Report (CSR)) upon request from qualified researchers, and subject to certain criteria, conditions, and exceptions. Further details on Pfizer's data sharing criteria and process for requesting access can be found at: https://www.pfizer.com/science/clinical\_trials/trial\_data\_and\_results/data\_requests.